The Pathological Mechanisms of Estrogen-Induced Cholestasis: Current Perspectives

Genetic prediction of the relationship between metabolic syndrome and colorectal cancer risk: a Mendelian randomization study

BACKGROUND

Despite a growing body of observational studies indicating a potential link between metabolic syndrome and colorectal cancer, a definitive causal relationship has yet to be established. This study aimed to elucidate the causal relationship between metabolic syndrome and colorectal cancer through Mendelian randomization.

METHODS

We screened for instrumental variables associated with metabolic syndrome and its diagnostic components and with colorectal cancer through the use of a genome-wide association study database, and conducted a preliminary Mendelian randomization analysis. To corroborate the dependability of our conclusions, an additional dataset was used for replication analysis in a Mendelian randomization method, which was further integrated with a meta-analysis.

RESULTS

Preliminary analysis using the inverse variance weighted method revealed positive correlations between metabolic syndrome (OR [95% CI] = 1.37[1.15-1.63], P = 5.02 × 10-4) and waist circumference (OR [95% CI] = 1.39[1.21-1.61], P = 7.38 × 10-6) and the risk of colorectal cancer. Replication analysis also revealed the same results: metabolic syndrome (OR [95% CI] = 1.24[1.02-1.51], P = 0.030) and waist circumference (OR [95% CI] = 1.23[1.05-1.45], P = 0.013). The meta-analysis results further confirmed the associations between metabolic syndrome (OR [95% CI] = 1.31[1.15-1.49], P < 0.001) and waist circumference (OR [95% CI] = 1.32[1.18-1.47], P < 0.001) and colorectal cancer.

CONCLUSION

Our study indicated that metabolic syndrome increases the risk of CRC, particularly in patients with abdominal obesity.

Molecular insights into experimental models and therapeutics for cholestasis

Cholestatic liver disease (CLD) is a range of conditions caused by the accumulation of bile acids (BAs) or disruptions in bile flow, which can harm the liver and bile ducts. To investigate its pathogenesis and treatment, it is essential to establish and assess experimental models of cholestasis, which have significant clinical value. However, owing to the complex pathogenesis of cholestasis, a single modelling method can merely reflect one or a few pathological mechanisms, and each method has its adaptability and limitations. We summarize the existing experimental models of cholestasis, including animal models, gene-knockout models, cell models, and organoid models. We also describe the main types of cholestatic disease simulated clinically. This review provides an overview of targeted therapy used for treating cholestasis based on the current research status of cholestasis models. In addition, we discuss the respective advantages and disadvantages of different models of cholestasis to help establish experimental models that resemble clinical disease conditions. In sum, this review not only outlines the current research with cholestasis models but also projects prospects for clinical treatment, thereby bridging basic research and practical therapeutic applications.

Ursodeoxycholic acid and 18β-glycyrrhetinic acid alleviate ethinylestradiol-induced cholestasis via downregulating RORγt and CXCR3 signaling pathway in iNKT cells

Estrogen-induced intrahepatic cholestasis (IHC) is a mild but potentially serious risk and urges for new therapeutic targets and effective treatment. Our previous study demonstrated that RORγt and CXCR3 signaling pathway of invariant natural killer T (iNKT) 17 cells play pathogenic roles in 17α-ethinylestradiol (EE)-induced IHC. Ursodeoxycholic acid (UDCA) and 18β-glycyrrhetinic acid (GA) present a protective effect on IHC partially due to their immunomodulatory properties. Hence in present study, we aim to investigate the effectiveness of UDCA and 18β-GA in vitro and verify the accessibility of the above targets. Biochemical index measurement indicated that UDCA and 18β-GA presented efficacy to alleviate EE-induced cholestatic cytotoxicity. Both UDCA and 18β-GA exhibited suppression on the CXCL9/10-CXCR3 axis, and significantly restrained the expression of RORγt in vitro. In conclusion, our observations provide new therapeutic targets of UDCA and 18β-GA, and 18β-GA as an alternative treatment for EE-induced cholestasis.

Pharmacokinetics and safety of first-line tuberculosis drugs rifampin, isoniazid, ethambutol, and pyrazinamide during pregnancy and postpartum: results from IMPAACT P1026s

Physiological changes during pregnancy may alter the pharmacokinetics (PK) of antituberculosis drugs. The International Maternal Pediatric Adolescent AIDS Clinical Trials Network P1026s was a multicenter, phase IV, observational, prospective PK and safety study of antiretroviral and antituberculosis drugs administered as part of clinical care in pregnant persons living with and without HIV. We assessed the effects of pregnancy on rifampin, isoniazid, ethambutol, and pyrazinamide PK in pregnant and postpartum (PP) persons without HIV treated for drug-susceptible tuberculosis disease. Daily antituberculosis treatment was prescribed following World Health Organization-recommended weight-band dosing guidelines. Steady-state 12-hour PK profiles of rifampin, isoniazid, ethambutol, and pyrazinamide were performed during second trimester (2T), third trimester (3T), and 2-8 of weeks PP. PK parameters were characterized using noncompartmental analysis, and comparisons were made using geometric mean ratios (GMRs) with 90% confidence intervals (CI). Twenty-seven participants were included: 11 African, 9 Asian, 3 Hispanic, and 4 mixed descent. PK data were available for 17, 21, and 14 participants in 2T, 3T, and PP, respectively. Rifampin and pyrazinamide AUC0-24 and C max in pregnancy were comparable to PP with the GMR between 0.80 and 1.25. Compared to PP, isoniazid AUC0-24 was 25% lower and C max was 23% lower in 3T. Ethambutol AUC0-24 was 39% lower in 3T but limited by a low PP sample size. In summary, isoniazid and ethambutol concentrations were lower during pregnancy compared to PP concentrations, while rifampin and pyrazinamide concentrations were similar. However, the median AUC0-24 for rifampin, isoniazid, and pyrazinamide met the therapeutic targets. The clinical impact of lower isoniazid and ethambutol exposure during pregnancy needs to be determined.

Sex-Dependent Differences in Cholestasis: Why Estrogen Signaling May Be a Key Pathophysiological Driver

Primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) are cholestatic liver diseases that have significant clinical impact with debilitating symptoms and mortality. While PBC is predominantly seen in perimenopausal and postmenopausal women, men who are diagnosed with PBC have worse clinical outcomes and all-cause mortality. In contrast, 60% to 70% of patients with PSC are men; the data indicate that female sex may be an independent factor against PSC-related complications. These findings suggest a sex-dependent biological basis for these differences. Estrogen has been implicated in the pathogenesis of intrahepatic cholestasis of pregnancy and may induce cholestasis through a variety of interactions. However, it is unclear why some sexual dimorphic features may provide a protective effect despite known estrogen models that induce cholestasis. This article provides a brief introductory background and discusses the sexual dimorphism in clinical presentation in PSC and PBC. It also explores the role of estrogen signaling in pathogenesis and how it relates to intrahepatic cholestasis of pregnancy. Studies have already targeted certain molecules involved in estrogen signaling, and this review discusses these studies that identify estrogen-related receptor, estrogen receptor-α, estrogen receptor-β, farnesoid X receptor, and mast cells as possible targets, in addition to long noncoding RNA H19-induced cholestasis and sexual dimorphism. It also explores these interactions and their role in the pathogenesis of PBC and PSC.

The increased risk of colorectal cancer in the women who underwent hysterectomy from the South Korean National Health Insurance Database

BACKGROUND

Several population-based studies and observational studies have shown that oophorectomy is associated with an increased risk of colorectal cancer (CRC), and hormone replacement therapy has been associated with a reduction in the risk of colorectal cancer. This study was carried out to investigate whether hysterectomy, which may affect the levels of female hormones, is associated with a risk of cancer of the specific gastrointestinal tract.

METHODS

This population-based retrospective cohort study was conducted using insurance data provided by the Health Insurance Review and Assessment Service (HIRA) from January 1, 2007, to December 31, 2020. The hysterectomy group included 40- to 59-year-old women who underwent hysterectomy with uterine leiomyoma or uterine endometriosis from January 1, 2011, to December 31, 2014. The control group included women aged 40 to 59 years who visited medical institutions for medical examination from January 1, 2011 to December 31, 2014.

RESULTS

The hysterectomy and non-hysterectomhy groups comprised 66,204 and 89,768 subjects, respectively. The median ages in the non-hysterectomy group and hysterectomy group were 48 (range: 43-53) and 46 (range: 44-49) years, respectively. In the unadjusted results of the analysis, all colorectal cancer (CRC) increased in the hysterectomy alone group (HR 1.222, 95% confidence interval (CI) 1.016-1.47, p = 0.033), sigmoid colon cancer increased in the hysterectomy alone group (HR 1.71, 95% CI 1.073-2.724, p = 0.024), and rectal cancer increased in the hysterectomy with adnexal surgery group (HR 1.924, 95% CI 1.073-2.724, p = 0.002). The adjusted results showed that all CRC increased in the hysterectomy alone group (HR 1.406, 95% CI 1.057-1.871, p = 0.019), colon cancer increased in the hysterectomy alone group (HR 1.523, 95% CI 1.068-2.17, p = 0.02), and rectal cancer increased in the hysterectomy with adnexal surgery group (HR 1.933, 95% CI 1.131-3.302, p = 0.016). The all-cause mortality of GI cancer increased in the hysterectomy alone group (HR 3.495, 95% CI 1.347-9.07, p = 0.001).

CONCLUSIONS

This study showed that the risk of all CRC increased in women who underwent hysterectomy compared with women who did not. In particular, the risk of rectal cancer was significantly higher in the women who underwent hysterectomy with adnexal surgery than in the controls. There was no association between hysterectomy and other GI cancers.

Placing steroid hormones within the human ABCC3 transporter reveals a compatible amphiphilic substrate-binding pocket

The human ABC transporter ABCC3 (also known as MRP3) transports a wide spectrum of substrates, including endogenous metabolites and exogenous drugs. Accordingly, it participates in multiple physiological processes and is involved in diverse human diseases such as intrahepatic cholestasis of pregnancy, which is caused by the intracellular accumulation of bile acids and estrogens. Here, we report three cryogenic electron microscopy structures of ABCC3: in the apo-form and in complexed forms bound to either the conjugated sex hormones β-estradiol 17-(β-D-glucuronide) and dehydroepiandrosterone sulfate. For both hormones, the steroid nuclei that superimpose against each other occupy the hydrophobic center of the transport cavity, whereas the two conjugation groups are separated and fixed by the hydrophilic patches in two transmembrane domains. Structural analysis combined with site-directed mutagenesis and ATPase activity assays revealed that ABCC3 possesses an amphiphilic substrate-binding pocket able to hold either conjugated hormone in an asymmetric pattern. These data build on consensus features of the substrate-binding pocket of MRPs and provide a structural platform for the rational design of inhibitors.

Abnormal alanine aminotransferase levels in patients with moderate or severe ovarian hyperstimulation result in an increased risk of obstetric complications

OBJECTIVES

To explore the effect of abnormally elevated serum alanine aminotransferase (ALT) on pregnancy outcomes in patients with moderate and severe ovarian hyperstimulation syndrome (OHSS) at disease onset.

METHODS

This was a single-center retrospective cohort study conducted between January 1, 2014 and October 31, 2021. A total of 3550 fresh in vitro fertilization/intracytoplasmic sperm injection embryo transfer cycles were included, using Golan's three-degree, five-level classification to diagnose patients with OHSS. According to the patient's ALT level after diagnosis of OHSS, 123 (3.46%) patients with moderate-to-severe OHSS were divided into two groups. A control group included 3427 (96.54%) non-OHSS patients, and 91 (2.56%) abnormal ALT patients were matched with the control group for propensity scores.

RESULTS

There was no difference in baseline data between the abnormal ALT and matched control groups. The incidence of obstetric complications was significantly higher in the abnormal ALT group than in the matched control group (P < 0.05). After adjusting for confounding factors, the incidence of obstetric complications in the abnormal ALT group was still higher than that in the normal ALT group (P < 0.05).

CONCLUSION

In patients with moderate and severe OHSS, higher ALT levels resulted in an increased risk of obstetric and neonatal complications.

Baohuoside I inhibits FXR signaling pathway to interfere with bile acid homeostasis via targeting ER α degradation

Epimedii folium (EF) is an effective herbal medicine in osteoporosis treatment, but the clinical utilization of EF has been limited due to potential hepatotoxicity. The previous studies identified that baohuoside I (BI), the main active component of EF, was relevant to EF-induced liver injury. However, the mechanisms of BI causing direct injury to hepatocytes remain unclear. Here, we reveal that BI inhibits FXR-mediated signaling pathway via targeting estrogen receptor α (ER α), leading to the accumulation of bile acids (BAs). Targeted bile acid analyses show BI alters the BA composition and distribution, resulting in impaired BA homeostasis. Mechanistically, BI induces FXR-dependent hepatotoxicity at transcriptional level. Additionally, ER α is predicted to bind to the FXR promoter region based on transcription factor binding sites databases and we further demonstrate that ER α positively regulates FXR promoter activity and affects the expression of target genes involved in BA metabolism. Importantly, we discover that ER α and its mediated FXR transcription regulation might be involved in BI-induced liver injury via ligand-dependent ER α degradation. Collectively, our findings indicate that FXR is a newly discovered target gene of ER α mediated BI-induced liver injury, and suggest BI may be responsible for EF-induced liver injury.

Sex Differences in the Pharmacokinetics of Cannabidiol and Metabolites Following Oral Administration of a Cannabidiol-Dominant Cannabis Oil in Healthy Adults

Introduction: Oral cannabidiol (CBD) product use is increasingly growing among women; however, there is a lack of data on sex differences in the pharmacokinetics (PKs) of CBD and its primary metabolites, 7-hydroxy-CBD (7-OH-CBD) and 7-carboxy-CBD (7-COOH-CBD), after repeated doses. Materials and Methods: The present study is a secondary analysis of data from a randomized, double-blind, placebo-controlled multiple-dose trial of a commercially available, CBD-dominant oral cannabis product. Healthy participants (n=17 males and 15 females) were randomized to receive 120 to 480 mg of CBD daily for 7 days. Dosing groups were pooled for all analyses due to sample size limitations. Analyses compared plasma PK parameters by sex, day, and sex×day. Results: For raw PK parameters for CBD and metabolites, there were no statistically significant effects of sex×day or sex (all p-values >0.05). For metabolite-to-parent ratios (MPRs) of AUC_0-t, there were significant effects of the sex×day interactions for 7-OH-CBD (F=6.89, p=0.016) and 7-COOH-CBD (F=5.96, p=0.021). For 7-OH-CBD, follow-up analyses showed significant simple effects of day within females (t=4.13, p<0.001), but not within males (t=0.34, p=0.73), such that 7-OH-CBD MPRs increased significantly from day 1 to 7 for females, but not for males. For 7-COOH-CBD, follow-up analyses revealed significant simple effects of day within females (t=8.24, p<0.001) and males (t=5.20, p<0.001), therefore 7-COOH-CBD MPRs increased significantly from day 1 to 7 in both sexes, but the increase was significantly greater among females than among males. Within dosing days, there were no statistically significant simple effects of sex on MPRs of 7-OH-CBD or 7-COOH-CBD. Conclusions: Females exhibited greater relative exposure to CBD metabolites in plasma over time, which may reflect sex differences in CBD metabolism or elimination. Further research assessing the safety implications of higher relative exposure to CBD metabolites over longer periods of time is warranted to mirror typical consumer use patterns.

Pathophysiological role of BACH transcription factors in digestive system diseases

BTB and CNC homologous (BACH) proteins, including BACH1 and BACH2, are transcription factors that are widely expressed in human tissues. BACH proteins form heterodimers with small musculoaponeurotic fibrosarcoma (MAF) proteins to suppress the transcription of target genes. Furthermore, BACH1 promotes the transcription of target genes. BACH proteins regulate physiological processes, such as the differentiation of B cells and T cells, mitochondrial function, and heme homeostasis as well as pathogenesis related to inflammation, oxidative-stress damage caused by drugs, toxicants, or infections; autoimmunity disorders; and cancer angiogenesis, epithelial-mesenchymal transition, chemotherapy resistance, progression, and metabolism. In this review, we discuss the function of BACH proteins in the digestive system, including the liver, gallbladder, esophagus, stomach, small and large intestines, and pancreas. BACH proteins directly target genes or indirectly regulate downstream molecules to promote or inhibit biological phenomena such as inflammation, tumor angiogenesis, and epithelial-mesenchymal transition. BACH proteins are also regulated by proteins, miRNAs, LncRNAs, labile iron, and positive and negative feedback. Additionally, we summarize a list of regulators targeting these proteins. Our review provides a reference for future studies on targeted drugs in digestive diseases.

Regulation of ABC transporters by sex steroids may explain differences in drug resistance between sexes

Drug efficacy is dependent on the pharmacokinetics and pharmacodynamics of therapeutic agents. Tight junctions, detoxification enzymes, and drug transporters, due to their localization on epithelial barriers, modulate the absorption, distribution, and the elimination of a drug. The epithelial barriers which control the pharmacokinetic processes are sex steroid hormone targets, and in this way, sex hormones may also control the drug transport across these barriers. Thus, sex steroids contribute to sex differences in drug resistance and have a relevant impact on the sex-related efficacy of many therapeutic drugs. As a consequence, for the further development and optimization of therapeutic strategies, the sex of the individuals must be taken into consideration. Here, we gather and discuss the evidence about the regulation of ATP-binding cassette transporters by sex steroids, and we also describe the signaling pathways by which sex steroids modulate ATP-binding cassette transporters expression, with a focus in the most important ATP-binding cassette transporters involved in multidrug resistance.

Calculus Bovis Sativus alleviates estrogen cholestasis-induced gut and liver injury in rats by regulating inflammation, oxidative stress, apoptosis, and bile acid profiles

ETHNOPHARMACOLOGICAL RELEVANCE

Natural Calculus Bovis (NCB) is a traditional Chinese medicine used for anti-inflammation, treating fever, pain, sedation, and recovering hepatobiliary function. Calculus Bovis Sativus (CBS), produced from in vitro artificial cultivation by bioengineering techniques, acts as an ideal substitute for NCB when treating various diseases.

AIM OF THE STUDY

Gut-liver injury is an important pathological feature of several cholestatic liver diseases, including estrogen-induced cholestasis (EIC). The strong link between cholestatic liver injury and intestinal damage emphasizes the need of considering gut-liver integrity during treatment. The purpose of this study is to look into the pharmacological activities of CBS on EIC-induced gut and liver damage.

MATERIALS AND METHODS

EIC-induced cholestatic rats were given oral gavage daily for five days with or without CBS (150 mg/kg). The liver/body weight, serum biochemistry, and tissue histopathology were then evaluated. Quantitative real-time PCR, Western blot analyses, and immunofluorescence were used to determine the gene expression associated with pathological alterations of the liver and intestine in EIC-induced cholestatic rats. Bile acid profiles within enterohepatic circulation were detected by liquid chromatography-mass spectrometry.

RESULTS

CBS significantly reduced relative liver weight, restored serum biochemistry levels, and improved the hepatic and intestinal pathological damage in EIC model rats. CBS reduced EIC-induced hepatic inflammation by inactivation of the NF-κB signaling and inhibition of TNFα, IL-1β, and IL-6 expression. CBS alleviated EIC-induced hepatic and intestinal oxidative stress by regulating Nrf2-GCLM/GCLC and Nrf2-HO-1 pathways, respectively. CBS treatment upregulated Bcl-2 and downregulated Bax and cleaved caspase3 to improve EIC-induced hepatic and intestinal cell apoptosis. Additionally, CBS reversed the disorders of bile acid profiles in the enterohepatic circulation by reducing bile acid accumulation in the liver and plasma and increasing bile excretion and intestinal reabsorption of bile acids.

CONCLUSION

CBS alleviates EIC-induced hepatic and intestinal injury through regulating inflammation, oxidative stress, apoptosis, and bile acid profiles. These results suggest that CBS or drugs targeting the gut-liver axis may be effective therapeutic agents for cholestasis.

Liver function in transgender persons: Challenges in the COVID-19 era

Transgender persons constitute a non-negligible percentage of the general population. Physical gender-transitioning in trans persons is mainly achieved with hormonal cross-sex therapy and sex reassignment surgeries that aim to align bodily appearance with gender identity. Hormonal treatment acts via suppressing the secretion of the endogenous sex hormones and replacing them with the hormones of the desired sex. The administration of testosterone is the typical masculinizing treatment in trans men, whilst trans women are routinely treated with estradiol agents in combination with anti-androgens or gonadotrophin-releasing hormone agonists if testes are present. Exogenous androgenic steroids, estradiol agents, and anti-androgens have been implicated in a series of hepatotoxic effects. Thus, liver integrity is a major concern with the long-term administration of cross-sex therapy. Hepatic tissue is susceptible to coronavirus disease 19 (COVID-19) through various pathophysiological mechanisms. Special consideration should be paid to minimize the risk of hepatic damage from the potential cumulative effect of COVID-19 and gender-affirming treatment in transgender patients. Appropriate care is significant, with continuous laboratory monitoring, clinical observation and, if needed, specific treatment, especially in severe cases of infection and in persons with additional liver pathologies. The pandemic can be an opportunity to provide equal access to care for all and increase the resilience of the transgender population.

Fluorescein clearance kinetics in blood and bile indicates hepatic ischemia-reperfusion injury in rats

Quantitative measurement of the degree of hepatic ischemia-reperfusion injury (IRI) is crucial for developing therapeutic strategies for its treatment. We hypothesized that clearance of fluorescent dye through bile metabolism may reflect the degree of hepatic IRI. In this study, we investigated sodium fluorescein clearance kinetics in blood and bile for quantifying the degree of hepatic IRI. Warm ischemia times (WITs) of 0, 30, or 60 min followed by 1 h or 4 h of reperfusion, were applied to the median and lateral lobes of the liver in Sprague-Dawley rats. Subsequently, 2 mg/kg of sodium fluorescein was injected intravenously, and blood and bile samples were collected over 60 min to measure fluorescence intensities. The bile-to-plasma fluorescence ratios demonstrated an inverse correlation with WIT and were distinctly lower in the 60-min WIT group than in the control or 30-min WIT groups. Bile-to-plasma fluorescence ratios displayed superior discriminability for short versus long WITs when measured 1 h after reperfusion versus 4 h. We conclude that the bile-to-blood ratio of fluorescence after sodium fluorescein injection has the potential to enable the quantification of hepatic IRI severity.NEW & NOTEWORTHY Previous attempts to use fluorophore clearance to test liver function have relied on a single source of data. However, the kinetics of substrate processing via bile metabolism include decreasing levels in blood and increasing levels in bile. Thus, we analyzed data from blood and bile to better reflect fluorescein clearance kinetics.

Ginsenosides improve reproductive capability of aged female Drosophila through mechanism dependent on ecdysteroid receptor (ECR) and steroid signaling pathway

Aging ovaries caused diminished fertility and depleted steroid hormone level. Ginsenosides, the active ingredient in ginseng, had estrogen-like hormonal effects. Although ginsenosides were well known for their ability to alleviate many age-related degenerative diseases, the effect of ginsenosides on the decline in reproductive capability caused by aging, as well as the mechanism, are unknown. We found that ginsenosides improved the quantity and quality of the offspring, prolonged life and restored muscle ability in aged female Drosophila. In addition, ginsenosides inhibited ovarian atrophy and maintained steroid hormone 20-Hydroxyecdysone (20E) and juvenile-preserving hormone (JH)) levels. Ginsenosides activated ecdysteroid receptor (ECR) and increased the expression of the early transcription genes E74 and Broad (Br), which triggered steroid signaling pathway. Meanwhile, ginsenosides promoted JH biosynthesis by increasing the expression of Hydroxyl-methylglutaryl-CoA reductase (HMGR) and juvenile hormone acid O-methyltransferase (JHAMT). Subsequently, JH was bound to Methoprene Tolerant (Met) and activated the transcription of the responsive gene Kruppel Homolog 1 (Kr-h1), which coordinated with 20E signaling to promote the reproduction of aged female Drosophila. The reproductive capacity and steroid hormone levels were not improved and the steroid signaling pathway was not activated in ginsenoside-treated ECR knockout Drosophila. This suggested that ginsenosides played a role dependent on targeted ECR. Furthermore, 17 kinds of ginsenoside monomers were identified from the total ginsenosides. Among them, Rg1, Re and Rb1 improved the reproductive capacity and steroid hormone levels of aged female Drosophila, which has similar effects to the total ginsenoside. These results indicated that ginsenosides could enhance the reproductive capacity of aged female Drosophila by activating steroid signals dependent on nuclear receptor ECR. In addition, ginsenoside monomers Rg1, Rb1 and Re are the main active components of total ginsenosides to improve reproductive ability. This will provide strong evidence that ginsenosides had the potential to alleviate age-induced reproductive degradation.