Postpartum Involution Research Articles

Determination of the impacts of supplemental dietary curcumin on post-partum uterine involution using pulsed-wave doppler ultrasonography in Zaraibi goat

This study aimed to evaluate the impacts of supplemental dietary curcumin on post-partum uterine involution using pulsed-wave Doppler ultrasonography in postpartum goats. Ten pluriparous Zaraibi goats were used and divided into two groups. Group 1 (n = 5; control) received only a base diet. Group 2 (n = 5; treated) received a base diet supplemented with curcumin (200 mg/kg diet) daily for 28 days, starting from day 1 postpartum (PP) till day 28 PP. Uterine morphometrical changes (uterine horn diameter; UHD and caruncle diameter; CD), uterine hemodynamics (resistance and pulsatility indices (RI and PI), systolic/ diastolic ratio (S/D), peak systolic velocity (PSV), end-diastolic velocity (EDV), blood flow volume (BFV), and blood flow rate (BFR)), and progesterone level were evaluated. Results revealed that the diameter of the uterine horn decreased rapidly from day 1 to day 10 PP (> 50%) but more steadily from day 14 to day 28 PP in both groups. After day 21 PP, there was nearly no reduction in UHD and CD in both groups. The treated group had lower values of the RI and PI (P < 0.05) than the control group. Regarding the BFR and BFV in the treated group, there was a significant increase (P < 0.05) on day 17 PP, then started to decrease till day 28 PP. While in the control group, there was a significant decrease (P < 0.05) in BFR and BFV from day 1 PP till day 28 PP. In conclusion, the incorporation of curcumin in the diet of PP Zaraibi goats improved reproductive performance via improvements in uterine morphometric changes as well as blood perfusion.

Formulation and Evaluation of Herbal Tablets from the Shimshin-6 Prescription and Its Effect on Postpartum Involution in Rats

The Shimshin-6 prescription has been used to treat female patients for blood clots, back and waist pain, and menstrual cramps. It is intended to support the recovery of the uterus after both childbirth and abortion. The purpose of this study is to create a tablet form of the Shimshin-6 formula and examine its effects on the recovery of the uterus after childbirth. The granules were developed using wet granulation, and the tablets were made using a direct compression method. Our test product in tablet form was manufactured following the quality parameters specified in the Mongolian National Pharmacopoeia. Shimshin-3 tablet was considered the best formulation; it used 5% cane sugar as a binder. In this study, Shimshin-6 treatment significantly reduced the uterus index and blood estrogen levels compared to the control group showing no difference in progesterone concentration. We found that Shimshin-6 decreased Tumor Necrosis Factor (TNFα) and regulated growth factors in postpartum rats. Shimshin-6 also regulated postpartum uterine recovery, as indicated by histological analysis. Our results showed the infiltration of inflammatory cell and hemorrhagic changes in the uterine wall. In conclusion, the formulation and evaluation of herbal tablets were satisfactory, and it has been found to enhance uterine recovery postpartum in rats.

Postpartum uterine involution promoted by penetrating-moxibustion therapy: a randomized controlled trial.

To observe the effect of penetrating-moxibustion therapy on postpartum uterine involution. Eighty puerpera were randomized into an observation group and a control group, 40 cases in each one. In the control group, oxytocin injection was administered by intravenous drip, 20 U each time, once daily. In the observation group, on the base of the treatment as the control group, the penetrating-moxibustion therapy was used at Shenque (GV 8), Qihai (CV 6) and Guanyuan (CV 4), 30 min to 40 min each time, twice a day. The intervention of each group started from the first day after childbirth and lasted 3 days. The uterine volume before and after treatment, and in 42 days of postpartum, the height decrease of the fundus of the uterus, the score of visual analogue scale (VAS) for uterine contraction, the volume of lochia rubra in 1 to 3 days of treatment, and lochia duration were compared between the two groups; and the clinical effect was evaluated. The uterine volume in the observation group was smaller than that of the control group after treatment (P<0.01). In 1 to 3 days of treatment, the height decrease of the fundus of the uterus in the observation group was larger (P<0.01), VAS scores of uterine contraction were lower (P<0.05, P<0.01), the lochia rubra volume was less (P<0.01) than those in the control group. The duration of lochia rubra and lochia was shorter (P<0.01) in the observation group when compared with that of the control group. The favorable rate of uterine involution in the observation group was 95.0% (38/40), higher than that of the control group (75.0%, 30/40, P<0.05). Penetrating-moxibustion therapy accelerates the recovery of the uterine volume, relieves uterine contraction, shortens the duration of lochia, reduces the lochia volume and promotes the postpartum uterine involution.

Specificity of two peripartum blood markers for early lactation acute uterine inflammation in pasture-fed, seasonal-calving dairy cows.

A delayed recovery of the reproductive tract from natural inflammatory processes associated with postpartum involution will compromise further reproductive function. Following a literature review, we selected serum amyloid A (SAA) and α1-acid glycoprotein (α1-AGP) to assess as potential circulating markers of acute uterine inflammation, as concentrations of these 2 acute phase proteins were reported to be elevated early postpartum in dairy cows with active uterine infection. Convenience serum samples from an induced model of uterine infection were used to measure concentrations of these markers. Infection was induced by infusing either 107 or 109 cfu of Trueperella pyogenes (n = 9 cows each; bacteria group n = 18) or saline as a control (n = 18) into the uterus at 48 d postpartum. Although infection stimulated an increase in uterine polymorphonuclear neutrophils, SAA and α1-AGP concentrations in serum were not different between infusion groups. Cows were subsequently classified into uterine health groups based on the presence of endometritis, with or without the presence of T. pyogenes in uterine culture in response to uterine infusion. Mean SAA concentrations were greater in cows that were either endometritis negative – infection positive (n = 9), endometritis positive – infection negative (n = 5), or endometritis positive – infection positive, compared with the endometritis negative – infection negative (n = 11) cows. There was no difference between uterine health groups for α1-AGP concentrations. Mean SAA and α1-AGP concentrations changed over time, reaching maximum concentrations on d 3 and 7 post-infusion, respectively, before decreasing thereafter to d 17 post-infusion.

396 Unraveling the Immunological Basis of Lobular Involution in Breast Cancer Development

OBJECTIVES/GOALS: Reveal common immune mechanisms in dysregulated age-related lobular involution (ARLI) and post-partum lobular involution (PPLI) to understand their link to increased breast cancer risk, challenging the traditional view of their distinctiveness. Ultimately, to improve breast cancer risk assessment and personalized prevention METHODS/STUDY POPULATION: The Mayo Clinic Benign Breast Disease (BBD) cohort comprises of ~20,000 women with benign biopsies, including ~1000 women with sequential benign biopsies. Lobular involution (LI) status was assessed by selecting perimenopausal women, ages 45-55, with sequential biopsies, comparing acini number and lobule size between initial and subsequent biopsies. NanoString IO360/ BC360 RNA profiling identified differentially expressed genes associated with dysregulated LI. Using multiplex immunofluorescence (mIF), I'll analyze and spatially map immune biomarkers related to dysregulated ARLI and PPLI in BBD tissue from perimenopausal women who did or did not go on to develop breast cancer, assessing the commonality of ARLI and PPLI markers and exploring their potential as risk biomarkers for breast cancer. RESULTS/ANTICIPATED RESULTS: Preliminary findings link patients who display dysregulated ARLI with an increased breast cancer risk and identify vital PPLI biomarkers in perimenopausal women. I expect the biopsies of women who developed post-menopausal breast cancer (PMBC) and post-partum breast cancer (PPBC) to exhibit elevated levels of dysregulated ARLI immune biomarkers and PPLI biomarkers. Spatially mapping these markers promises to provide a more comprehensive understanding of their interactions, potentially revealing common immunological pathways. These findings could transform our current paradigm of ARLI and PPLI as distinct processes and demonstrate their interconnection in shaping breast cancer risk. DISCUSSION/SIGNIFICANCE: PMBC and PPBC dominate majority of breast cancer cases. Both involve activation of the understudied process of lobular involution, which has been shown to have pro-tumorigenic traits. Elucidating these mechanisms will aid more efficient risk stratification and personalized prevention to reduce incidence and mortality of breast cancer.

Abstract 849: Deciphering the link between aging, lobular involution, and breast cancer risk: The role of LIFR/pSTAT3 signaling

Abstract Background: Age-related lobular involution (ARLI), characterized by regression of breast epithelial tissue during the peri-and post-menopausal period, plays a crucial role in breast cancer risk. Delayed or incomplete ARLI is linked with increased postmenopausal breast cancer susceptibility.This study focuses on unraveling the molecular mechanisms of ARLI, drawing parallels with the well-characterized postpartum involution (PPI). Our aim was to discover biomarkers differentiating women who progressed through ARLI from those with stagnant ARLI. Methods: We utilized the Mayo Clinic Benign Breast Disease (BBD) cohort, analyzing 108 perimenopausal women aged 45-55 who had a subsequent benign biopsy between 2-15 years later. We assessed Lobular Involution (Ll) status by comparing the number and size of lobules in initial and subsequent biopsies. RNA profiling of initial biopsies was performed using NanoString 10360 and BC360, identifying differentially expressed genes between ARLI progression and stagnation. Immunohistochemistry (IHC) mapped the expression of these biomarkers in epithelial lobules. Results: We identified 37 genes with significant differential expression, highlighting Leukemia Inhibitory Factor Receptor (LIFR) as upregulated in ARLI stagnant samples. LIFR, part of the IL-6 cytokine signaling pathway, is known for its role in the induction of apoptosis during PPI via pSTAT3 activation. Our IHC analyses of initial biopsies of women who differentially progress through ARLI confirmed differential expression of LIFR that is coordinately regulated with pSTAT3. Conclusion: Our findings reveal significant parallels between ARLI and PPI. Future research will assess how LIFR/pSTAT3 signaling is linked to induction of apoptotic markers in perimenopausal women and will investigate how anomalies in the LIFR/pSTAT3 pathway might contribute to heightened breast cancer risk in women with delayed or incomplete ARLI. This study not only sheds light on the complex biological processes of aging in breast tissue but also opens new avenues for breast cancer risk assessment and prevention strategies. Citation Format: Jaida C. Lue, Derek Radisky, Melody Stallings-Mann, Mark Sherman, Amy Degnim, Bryan McCauley, Tanya Hoskin. Deciphering the link between aging, lobular involution, and breast cancer risk: The role of LIFR/pSTAT3 signaling [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 849.

Abstract IA06: Postpartum breast involution informs breast cancer metastasis to the liver

Abstract Young women with breast cancer have disproportionally higher rates of metastasis, and effective treatment strategies are lacking. Our lab has focused on investigating how normal reproductive changes in tissue biology interface with breast cancer metastasis in young patients. These studies identify weaning-induced involution of the breast as a tissue remodeling process similar to wound healing that promotes metastasis in rodent models. Relevance to women is suggested by the fact that a breast cancer diagnosis within 5 years of childbirth is a strong and independent risk factor for metastasis. Further, these studies find that up to 50% of all young onset breast cancer is diagnosed within this high risk postpartum window. This subset of common, young onset breast cancer is referred to as postpartum breast cancer (PPBC). We find that PPBC appears durably altered by involution, as PPBC tumors display involution, metastatic, and treatment resistant molecular signatures. PPBC also specifically associates with increased liver metastases, a metastatic site associated with very poor prognosis. In rodents, we identified a functional link between the mammary gland and the liver, including weaning-induced liver involution. Liver involution is characterized by hepatocyte cell death, fibroblast activation, ECM deposition, and an immune regulatory infiltrate similar to that found in the postpartum involuting breast. In rodent models of breast cancer liver metastasis (BCLM), the involuting liver supports outgrowth of circulating breast cancer cells more than the nulliparous host liver. Evidence for similar liver biology occurring in women is suggested by studies in healthy women, where we find liver volume increase during pregnancy and loss post wean, data consistent with liver involution. In our mouse models of BCLM, the involution metastatic advantage coincided with weaning-induced immune tolerance in the liver. We next targeted the pro-tumor, immune suppressed state of involution with the immune modulatory agent vitamin D. These studies revealed dramatic down regulation of liver metabolism with weaning, including liver cytochrome P450 enzymes, which effectively nullified the protective effect of vitamin D in involution hosts. Combined, these novel findings are anticipated to have implications for sex-specific liver diseases broadly, efficacy of pro-drugs in the postpartum window, and for breast cancer outcomes in young patients. Citation Format: Pepper Schedin. Postpartum breast involution informs breast cancer metastasis to the liver [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Breast Cancer Research; 2023 Oct 19-22; San Diego, California. Philadelphia (PA): AACR; Cancer Res 2024;84(3 Suppl_1):Abstract nr IA06.

Abstract B079: Vitamin D metabolism is suppressed postpartum: Implications for targeting the postpartum window for cancer prevention

Abstract Postpartum mammary gland involution is a physiologic inflammatory process that associates with increased risk of postpartum breast cancer (PPBC). Pre-clinical studies provide rationale for targeting this pro-tumor window of involution for PPBC prevention. However, the liver also undergoes physiological remodeling after weaning—consistent with weaning-induced mammary gland involution—which could potentially impact the efficacy of anti-cancer prodrugs administered during the postpartum period. Here, we used mouse models to test the efficacy of vitamin D, a prodrug with known anti-cancer properties, during the postpartum period. Vitamin D supplementation is of particular interest due to its inclusion in dietary guidelines for postpartum women, where vitamin D deficiency is prevalent. Dietary vitamin D is biologically inactive and requires hydroxylation in the liver by Cyp2r1 to produce its circulating form (25(OH)D), which is further hydroxylated in the kidneys to produce the active form (1,25(OH)2D). To understand the impact of liver involution on vitamin D hydroxylation, RNAseq was performed on livers collected from nulliparous or involution mice. Expression of Cyp2r1 was 2-fold lower in involution livers, compared to nulliparous livers (p&amp;lt;0.001). Further, Cyp24a1, which is responsible for degradation of active vitamin D, was increased 5.5-fold in involution livers compared to nulliparous livers (p&amp;lt;0.001). These findings suggest that vitamin D supplementation would be ineffective in the postpartum period. Indeed, nulliparous mice supplemented with vitamin D showed a &amp;gt;2-fold increase in serum 25(OH)D (67.4±8.1nmol/L) compared to nulliparous mice fed a deficient diet (28.7±11.7nmol/L, p&amp;lt;0.01). In contrast, supplementation of involution mice did not increase serum 25(OH)D (supplemented=46.6±8.7nmol/L, deficient=33.7±8.5nmol/L, p&amp;gt;0.05). In the liver, tissue-specific concentrations of 25(OH)D were lower in supplemented involution mice (1.3±0.6ng/g), compared to supplemented nulliparous mice (2.0±0.4ng/g; p=0.02). To assess whether suppression of vitamin D metabolism impacts the anti-cancer activity of dietary vitamin D, mammary cancer cells (D2A1, 2 × 104 cells) were injected into mammary fatpads of mice. In nulliparous mice, vitamin D supplementation associated with a 3-fold reduction in tumor growth (p=0.03); whereas no anti-cancer effects were observed in involution mice. These findings suggest the anti-cancer effects of vitamin D are blocked postpartum due to suppression of vitamin D metabolism in the liver. Understanding how the postpartum liver metabolizes drugs is essential for targeting treatments to this window. A retrospective analysis of our RNAseq data identified 22 additional Cytochrome P450 (CYP450) enzymes—key players in drug metabolism—whose expression was regulated by reproductive stage, suggesting that the effect of liver involution extends beyond suppressed vitamin D metabolism. These findings highlight the importance of considering the postpartum involution period in the design and administration of pharmacological interventions. Citation Format: Sarah M Bernhardt, Pepper Schedin. Vitamin D metabolism is suppressed postpartum: Implications for targeting the postpartum window for cancer prevention [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Breast Cancer Research; 2023 Oct 19-22; San Diego, California. Philadelphia (PA): AACR; Cancer Res 2024;84(3 Suppl_1):Abstract nr B079.

User Satisfaction with Application for Postpartum Maternal Gymnastics (SIMPOR)

Introduction: Bleeding is the main cause of 50%-60% morbidity and mortality in the postpartum period due to imperfect myometrial contraction. Postpartum exercise is one of the actions of maximizing uterine contractions. It's accelerate uterine involution. Technology development very fast today, improvement of postpartum android base application that's applicable, educative and informative is needed. This study aims to develop a postpartum maternal exercise application (SIMPOR) for postpartum mothers using Android then test them until obtaining descriptions about satisfaction with the SIMPOR application. Methods: This study used a Research and Development method (R&amp;D) with 152 respondents taken by proportional stratified random sampling. Data analysis was chi-square with univariate and bivariate. Results: The majority of participants were aged in 20-40 years old (98%), educational majority in higher education (59.9%), most of the respondents were housewives (65.8%), having more than one toddler (77.6%), and the average of toddler age was less than 2 years old (84.2%). Most of the respondents' satisfaction with the SIMPOR application was very satisfied (88.16%); 3) There was a relationship between mother's work, parity, and the smallest child age on the satisfaction of using the SIMPOR application with pvalue&lt;0.05. Conclusion: Participants were very satisfied with this SIMPOR application. Based on that result, hopefully postpartum mothers can use this application as postpartum exercise guidance and to monitor their process postpartum period involution.

Adrenergic effect on women's blood neutrophil oxidative activity the first day after delivery.

Recent studies have described a significant role for neutrophils in reproductive processes and their participation in the preparation of the cervix for childbirth and the activation of labor, in the postpartum involution of the uterus, and in the occurrence of preeclampsia. This study aimed to assess the formation of free radicals by neutrophils in the blood of women on the first day after childbirth and to characterize the adrenergic effect on this process. Venous blood samples from 100 female volunteers aged 26-32 years who had 2 or 3 full-term deliveries were collected and analyzed. Various adrenergic compounds were considered (agonists alphaand betaadrenoreceptors, adrenoblockers). The intensity of the respiratory burst of neutrophils and the effect of adrenergic substances on them were assessed with latex-induced luminol-dependent chemiluminescence. Neutrophil activity depends on the stage of the woman's reproductive process: it decreases during pregnancy, reaches the lowest values during childbirth, and increases significantly in the first hours after childbirth. On the first day after childbirth, alpha-1-adrenergic receptors are highly active in neutrophils, through which NADP-H-oxidase is activated and activated oxygen species are formed. At the same time, alphaor beta-agonists inhibit the radical activity of cells. Latex-induced oxidative burst of female blood neutrophils correlates with the stage of the reproductive process. Stressful conditions in the postpartum period can suppress the ability of neutrophils to release reactive oxygen species, which increases the risk of postpartum infections.

МОРФОЛОГИЧЕСКИЕ ИЗМЕНЕНИЯ МИОМЕТРИЯ ВО ВРЕМЯ БЕРЕМЕННОСТИ И В ОТДАЛЕННОМ ПОСЛЕРОДОВОМ ПЕРИОДЕ В УСЛОВИЯХ ОСТРОГО ТОКСИЧЕСКОГО ГЕПАТОЗА И КОРРЕКЦИИ ИММОБИЛИЗИРОВАННОЙ ГИАЛУРОНИДАЗОЙ У МЫШЕЙ

Introduction. The prevalence of acute and chronic liver diseases in pregnant women increases every year, which is associated with a high risk of adverse outcome for the mother and fetus. At the same time, the mechanisms that ensure an increase in uterine mass, structural changes in the myometrium before childbirth and the process of postpartum involution of the uterus to the initial mass, the participation of molecular cellular mechanisms in pregnant women with liver pathology, and ways to correct it remain poorly understood. Aim. The aim of the study was to investigate morphological changes in the myometrium, during pregnancy and the late postpartum period in the myometrium of mice with acute CCl4-induced hepatosis and under conditions of its correction with immobilized hyaluronidase. Materials and methods. The experiment was performed on 200 female pregnant mice of the C57B1/6 line at two months of age. Acute toxic hepatosis was modeled by a single injection of tetrachlormethane. Correction of acute hepatosis was performed on the next day after administration of tetrachloromethane and subsequent days of pregnancy with a single injection of immobilized hyaluronidase. The animals were divided into 4 groups: a group with physiological pregnancy, animals with the immobilized hyaluronidase drug injection; animals with acute hepatosis; animals with acute hepatosis treated with immobilized hyaluronidase. Uterine samples were collected on the 18th, 21st days of pregnancy and on the 1st, 5th, 10th, 15th days after delivery. Results. The volume density (Vv) of myocytes in the state of apoptosis, interstitial cytoplasmic conglomerates, which are products of clasmacytosis, and necrotized myocytes were calculated, as well as the numerical density (Nai) of myocytes with positive expression of the p53 protein. Under conditions of acute hepatosis, structural transformations of the myometrium in the form of an increase in clasmacytosis, necrotized myocytes occur already during pregnancy. The main structural mechanism of the process of postpartum involution of the myometrium of mice in conditions of acute hepatosis in the long-term period of postpartum involution was clasmacyto sis and, to a lesser extent, necrosis of myocytes. The processes of myometrial involution in mice under conditions of acute hepatosis slow down and do not complete by the 15th day of the postpartum period. When correcting acute hepatosis with immobilized hyaluronidase, the volume density of cytoplasmic conglomerates, apoptotically altered myocytes and necrotized myocytes decreases from the 1st to the 15th day of the postpartum period, which indicates the completeness of postpartum uterine involution. Conclusion. Liver damage is accompanied by a change in the metabolism of sex hormones, which leads to an abnormality of the mechanisms of postpartum involution of the uterus, as well as its structural changes before childbirth.

Effect of 1,25-dihydroxyvitamin D3-glycosides on postpartum health, uterine involution and litter performance of sows in a free farrowing system

BackgroundVitamin D is essential for the reproductive efficiency in animals. There are indications that 1,25-vitD influenced the farrowing process and thus can decrease postpartum health problems. Therefore, the aim of this study was to investigate the effect of 1,25-vitD on postpartum health of the sow and uterine involution as well as the litter performance.ResultsThe rectal body temperature in the 1,25-vitD group was significantly (p < 0.05) lower during the first five days after farrowing compared to the negative control group (D1: 38.6 vs. 38.9 °C; D2: 38.5 vs. 38.7 °C; D3: 38.4 vs. 38.7 °C; D4: 38.4 vs. 38.6 °C; D5: 38.5 vs. 38.9 °C). Although there was no difference between the live born piglets after farrowing, a significant higher number of piglets at day 7 and at weaning (Dw) was detected in the 1,25-vitD group compared to the control group (D7: 14.1 ± 0.9 vs. 13.4 ± 1.0, p = 0.002; Dw: 14.0 ± 0.9 vs. 13.4 ± 1.0, p = 0.02). Furthermore, the litter weight gain was significantly higher in the 1,25-vitD group when compared to the control group (94.3 vs. 86.4 kg; p = 0.045), and the weight loss of the sows was significantly lower (52 vs. 59 kg; p = 0.03). No differences in other parameter were detected.ConclusionThis study showed a positive effect of 1,25-vitD on the body temperature, the litter performance and the body condition of the sows during lactation in comparison with the negative control group. However, more studies are needed to describe the mechanism of 1,25-vitD in detail.

Abstract B002: A facilitating role for semaphorin-7a in regulating cell invasion and matrix remodeling for DCIS progression

Abstract Approximately 25% of newly diagnosed breast cancer cases are non-invasive or pre-invasive breast cancers known as ductal carcinoma in situ (DCIS). DCIS can progress to invasive ductal carcinoma (IDC), conferring a more dangerous prognosis; however, there is a gap in knowledge regarding what ultimately causes this transition. Understanding epithelial invasion in the mammary gland will provide insight on how DCIS ultimately progresses to IDC. Our lab has found that DCIS transforms to IDC under the “wound-healing” pressure of postpartum tissue remodeling – termed postpartum mammary gland involution. This invasive transformation is dependent, in part, on collagen-induced cyclooxygenase (COX2) expression. We identified that a membrane-bound signaling molecule, semaphorin-7a (SEMA7A), promotes both collagen deposition and COX-2 expression and therefore DCIS progression. SEMA7A is also naturally upregulated in mammary epithelial cells during postpartum involution and in DCIS relative to normal epithelium. We have identified that inhibition or silencing of SEMA7A can inhibit DCIS invasion. While this demonstrates that SEMA7A expression is sufficient to promote innate capacity for tumor cell invasiveness, we have yet to investigate how SEMA7A interacts with the tumor microenvironment (TME) to promote stromal changes known to advance this transition, such as collagen remodeling or immune cell recruitment. We have demonstrated a potential role for DCIS-associated macrophages in facilitating this transition. Additionally, we have found that SEMA7A polarizes macrophages to an M2-like state, and this promotes remodeling of the lymphatic vasculature as well as tumor cell entry into lymphatic vessels. Furthermore, we have shown that SEMA7A promotes expression of matrix remodeling enzymes that can, in turn, promote shedding of SEMA7A into the TME where it can affect other cell types. We are utilizing intravital imaging to visualize tumor/lymphatic/macrophage interactions as well as second harmonic imaging to visualize SEMA7A-dependent changes in the collagen structure surrounding DCIS lesions. Our results suggest that SEMA7A mediates DCIS invasion through both intrinsic and extrinsic mechanisms, which could facilitate progression to metastasis. By understanding how SEMA7A regulates DCIS progression we can begin to introduce potential targets for preventative therapies for development of invasive disease – including targeting SEMA7A itself. Since SEMA7A is low in most adult tissues it is expected that such a therapeutic would be less toxic for patients than the current prescribed therapies. Citation Format: Petra Dahms. A facilitating role for semaphorin-7a in regulating cell invasion and matrix remodeling for DCIS progression [abstract]. In: Proceedings of the AACR Special Conference on Rethinking DCIS: An Opportunity for Prevention?; 2022 Sep 8-11; Philadelphia, PA. Philadelphia (PA): AACR; Can Prev Res 2022;15(12 Suppl_1): Abstract nr B002.

Oxylipins as Potential Regulators of Inflammatory Conditions of Human Lactation.

Chronic low-grade inflammation can be associated with obesity or subclinical mastitis (SCM), which is associated with poor infant growth in low- to middle-income country settings. It is unknown what physiological mechanisms are involved in low milk supply, but our research group has shown that mothers with low milk supply have higher inflammatory markers. Studies investigating oxylipin signaling have the potential to help explain mechanisms that mediate the impacts of inflammation on milk production. Animal studies have reported various elevated oxylipins during postpartum inflammation, mastitis, and mammary involution in ruminant models. Several investigations have quantified oxylipins in human milk, but very few studies have reported circulating oxylipin concentrations during lactation. In addition, there are technical considerations that must be addressed when reporting oxylipin concentrations in human milk. First, the majority of milk oxylipins are esterified in the triglyceride pool, which is not routinely measured. Second, total milk fat should be considered as a covariate when using milk oxylipins to predict outcomes. Finally, storage and handling conditions of milk samples must be carefully controlled to ensure accurate milk oxylipin quantitation, which may be affected by highly active lipases in human milk.

The postpartum uterine ultrasonographic scale in assessment of uterine involution after cesarean section in treated thrombophilia pregnant patients at term.

BackgroundPregnancy is a prothrombotic condition which can be abnormally exaggerated in women with thrombophilia.MethodsIn a prospective study, patients who delivered at term, by cesarean section, between 1 October 2017 and 1 December 2021, who already had a diagnosis of thrombophilia before coming to our hospital, were included in the study group (n = 80). A similar number of nonthrombophilia patients (n = 80) without any history of thrombotic events, age‐ and para‐matched with the study group, were included in the control group. The postpartum uterine ultrasonographic scale (PUUS) values, in the first 24–48 h, were correlated with the patients' data.ResultsThe P‐LCR (platelet large cell ratio), was significantly higher in the treated thrombophilia group (p = 0.042). There was no correlation between PUUS and complete blood count values, coagulation factors, maternal characteristics, or fetal outcomes, except for postpartum neutrophils (p = 0.047) and postpartum platelet count (p = 0.046).ConclusionsPostpartum uterine involution was not significantly different, after cesarean section, between treated thrombophilia patients and nonthrombophilia patients. Involution correlated only with postpartum neutrophils and postpartum platelet count.

Towards defining morphologic parameters of normal parous and nulliparous breast tissues by artificial intelligence

BackgroundBreast terminal duct lobular units (TDLUs), the source of most breast cancer (BC) precursors, are shaped by age-related involution, a gradual process, and postpartum involution (PPI), a dramatic inflammatory process that restores baseline microanatomy after weaning. Dysregulated PPI is implicated in the pathogenesis of postpartum BCs. We propose that assessment of TDLUs in the postpartum period may have value in risk estimation, but characteristics of these tissues in relation to epidemiological factors are incompletely described.MethodsUsing validated Artificial Intelligence and morphometric methods, we analyzed digitized images of tissue sections of normal breast tissues stained with hematoxylin and eosin from donors ≤ 45 years from the Komen Tissue Bank (180 parous and 545 nulliparous). Metrics assessed by AI, included: TDLU count; adipose tissue fraction; mean acini count/TDLU; mean dilated acini; mean average acini area; mean “capillary” area; mean epithelial area; mean ratio of epithelial area versus intralobular stroma; mean mononuclear cell count (surrogate of immune cells); mean fat area proximate to TDLUs and TDLU area. We compared epidemiologic characteristics collected via questionnaire by parity status and race, using a Wilcoxon rank sum test or Fisher’s exact test. Histologic features were compared between nulliparous and parous women (overall and by time between last birth and donation [recent birth: ≤ 5 years versus remote birth: > 5 years]) using multivariable regression models.ResultsNormal breast tissues of parous women contained significantly higher TDLU counts and acini counts, more frequent dilated acini, higher mononuclear cell counts in TDLUs and smaller acini area per TDLU than nulliparas (all multivariable analyses p < 0.001). Differences in TDLU counts and average acini size persisted for > 5 years postpartum, whereas increases in immune cells were most marked ≤ 5 years of a birth. Relationships were suggestively modified by several other factors, including demographic and reproductive characteristics, ethanol consumption and breastfeeding duration.ConclusionsOur study identified sustained expansion of TDLU numbers and reduced average acini area among parous versus nulliparous women and notable increases in immune responses within five years following childbirth. Further, we show that quantitative characteristics of normal breast samples vary with demographic features and BC risk factors.

Postpartum Involution of Mouse Myometrium in Acute CCl4-Induced Hepatosis and Its Correction with Immobilized Hyaluronidase.

We studied structural rearrangement of the myometrium of C57BL/6 mice during the postpartum period under conditions of acute toxic hepatosis induced by CCl4 injection and its correction with immobilized hyaluronidase. In contrast to physiological pregnancy, involution of the myometrium in mice under conditions of acute toxic hepatosis were not completed by the 10th day of the postpartum period. When toxic hepatosis was corrected with immobilized hyaluronidase, the main mechanism of postpartum involution of the mouse myometrium was clasmacytosis, the process of postpartum involution was significantly accelerated, but not completed by the 10th day, probably due to reduced vascularization of the myometrium.

FLUORESCENCE-HISTOCHEMICAL CHARACTERISTICS OF RAT’S UTERINE MAST CELLS DURING ITS POSTPARTUM INVOLUTION

The uterus is a unique organ of its kind due to the constant remodeling during the reproductive period of the tissues that make it up. Violations of the involution processes occurring in this organ after part can cause the development of pathological conditions of the uterus. The relevance of the study is determined by the active participation of biogenic amines in the regulation of tissue homeostasis and uterine histogenesis. The aim of the work was to study the patterns of spatial cooperation of mast cells in the uterus of rats and the content of catecholamine, serotonin and histamine in them during the postpartum period. Using fluorescent-histochemical methods, mast cells of the uterus of rats were studied in 100 outbred female rats of reproductive age, divided into 11 groups according to the postpartum period. The study was performed on cryostat sections of preparations of the uterine body. The density of the spatial distribution of endometrial and myometrium mast cells was assessed. The content of histamine, serotonin and catecholamine was determined by cytospectrofluorimetry in conventional units of the recording device in the cells. As a result of the study, it was found that the density of the spatial distribution of fluorescent mast cells in the mucosa and muscular layers of the uterine body is minimal on the first day after childbirth. The largest number of mast cells is observed on the 10th day after birth. The content of histamine, serotonin and catecholamine in the mast cells of the myometrium of the uterine body is maximum on the first day after birth and gradually decreasing, reaching the lowest values ​​on the 10–15th day of postpartum involution. Mast cells of the endometrium are characterized by a higher saturation of serotonin and catecholamine compared to the myometrium. In tissue basophils of the myometrium, a higher level of histamine is noted. Correlations of changes in the content of bio amines have been established. The density of the spatial distribution of mast cells of the endometrium and myometrium and the content of neurotransmitter bioamines in them during the postpartum involution of the uterus changes unidirectional, despite regional differences. It is possible that mast cells contribute to the restoration of sympathetic innervation of the uterus in the postpartum period.

Abstract P2-11-14: Pathology AI features and immune biomarkers of postpartum involution: Implications for postpartum breast cancer

Abstract Breast cancer risk is increased in parous women in the period following childbirth, peaking at five years. After weaning or in the absence of lactation, the breast undergoes postpartum involution (PPI), a process characterized by epithelial cell death and tissue remodeling that returns the mammary gland to a baseline state, and has previously been associated with increased inflammation and breast cancer development and progression in preclinical models. Features of PPI and determinants of related inflammation have been incompletely characterized among women. In this study, we performed visual and AI analysis of 725 digitized H&amp;E images of normal breast tissues donated to the Komen Tissue Bank (KTB) by parous and nulliparous women ≤45 years, and further investigated the immune microenvironment in specimens from 23 women (also from KTB, 13 parous, 10 nulliparous) using NanoString RNA immuno oncology (IO) 360 panels and immune protein biomarkers by NanoString GeoMx Digital Spatial Profiling (DSP). We found that recently parous women (≤5 years of a last birth) had higher numbers of terminal duct lobular units (TDLUs), immune cells, and plasma cells as compared with nulliparous women, and that beyond 5 years of a last birth, TDLU numbers were still higher in parous women, but the immune and plasma cell content of the breast of parous and nulliparous women were not significantly different. Our gene expression analysis revealed differential expression of genes that clustered according to parity status, with interferon stimulated genes; STAT1 and IFITM1, and interferon alpha receptor 1 (IFNAR1), and MHC class II genes (HLA-DMA, HLA-DPA,HLA-DPB1, and HLA-DRA) elevated in parous women. Our DSP analysis revealed that immune biomarkers with immunosuppressive functions, including ARG1, VISTA, CTLA-4, and CD68 were significantly higher in parous women as compared with nulliparous women. Breast tissues of parous women show lobular expansion and alterations in immune cell components compared with nulliparous tissues. Further research is needed to assess how these alterations may impact risk. Citation Format: Joshua Were Ogony, Thomas De Bel, Derek Radisky, Jeroen VanderLaak, Mark Sherman. Pathology AI features and immune biomarkers of postpartum involution: Implications for postpartum breast cancer [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P2-11-14.

Apios americana Medikus: A novel and promising food for postpartum uterine involution

AbstractPregnancy is a prolonged and tortuous process impairing puerperal health and life, in which uterine involution playing a decisive role. However, puerperae continually suffer from postpartum complications, whereas few research has focused on the postpartum recovery and uterine involution acceleration. The requirement for a safer and efficient therapy strategy for postpartum care is very urgent. The objective of this study was to explore the effects of Apios americana Medikus tuber to be a novel adjuvant therapy strategy for postpartum recovery. As a natural resource supplement, AM possesses multiple bioactivities and high biosafety, which also more acceptable for long treatment period during and after pregnancy. AM significantly altered the levels of estrogen, progesterone and their receptors, the secretion of transforming growth factor, matrix metalloproteinases, and inflammatory cytokines. In addition, it also significantly regulated various genes related to glucose and lipid metabolism, inflammation, and cell cycle, such as PLA2G3, EGR1, LCN2, and MMP9, thereby inhibiting inflammation and facilitating postpartum recovery and uterine involution. To conclude, our results suggested that AM as a promising supplementary food or a potential adjuvant treatment to accelerate postpartum uterine involution.