Bile Acid Sequestrants Research Articles

Comparison of Lp(a) assessment in patients with atherosclerotic cardiovascular disease between office-based cardiologists and general practitioners

Abstract Background Elevated lipoprotein(a) (Lp(a)) levels are a major risk factor that contribute to the development of ASCVD. Different guidelines for the treatment of patients with hypercholesterolemia are available in Germany. The German Cardiac Society recognized the 2019 ESC/EAS guideline for the management of dyslipidemia and endorses the measurement of Lp(a) at least once in a lifetime to identify those with very high inherited Lp(a) levels >180 mg/dL (>430 nmol/L) . The Nationale Versorgungsleitlinie, however, does not recommend testing of Lp(a). Methods and Objectives LipidSnapshot is a joint research project consisting of two parts. Part 1 is a prospective, non-interventional multicenter research project at office-based cardiologists (OBCs). Data from 1500 adults with known coronary artery disease, peripheral artery disease, prior myocardial infarction and/or ischemic stroke are collected from selected 49 OBCs. The second part is a retrospective, aggregated analysis of anonymous electronic medical records of 82.375 adult outpatient ASCVD patients documented by general practices (GPs) obtained from the IQVIA Disease Analyzer (note: 54% do not provide information on Lp(a) data to IQVIA). Availability of Lp(a) tests and lipid-lowering therapies (LLTs) in ASCVD patients with available LDL-C values within a 12-month period (July 2022-June 2023) were assessed. One of the objectives of LipidSnapshot is to compare the proportion of Lp(a) assessments in ASCVD patients documented by OBCs and GPs and to evaluate gender-, age- and LLTs-related differences in Lp(a) availability in patients documented by OBCs compared to GPs. Results Patients treated by OBCs were on average 72.4 (standard deviation (SD) 10.0) years old and 75.8 % were male while patients in the IQVIA dataset were on average 73.0 (SD 13.2) years old and 60.5% were male. The age distribution was comparable between both specialties. OBCs documented Lp(a) in 20.3% of their ASCVD patients, while only 3.0% of ASCVD patients documented by GPs had Lp(a) values documented. The testing rates in male and female patients were comparable between both specialties (OBC: 19.5 vs. 22.9%; GPs: 3.4 vs. 2.5%). For both specialties, Lp(a) testing rate was higher in younger patients compared to older patients (Table 1) and in patients treated with PCSK9-inhibitors (monoclonal antibodies, inclisiran), either as monotherapy or in combination with statins and/or other LLTs (ezetimibe, bempedoic acid, bile acid sequestrants) (Table 2). Conclusion The first snapshot revealed differences in healthcare provision of GPs compared to selected OBCs with lower rates of identification of higher risk patients treated by GPs in Germany.Age-related differences in Lp(a)LLT-related differences in Lp(a)

Efficacy of Bile Acid Sequestrants in the Treatment of Bile Acid Diarrhea: A Meta-Analysis of Randomized Controlled Trials.

Bile acid sequestrants (BASs) have often been used for bile acid diarrhea (BAD) but carry a high risk of adverse events. New generations of BASs show promising results; however, their efficacy remains unclear. This systematic review and meta-analysis was conducted using PubMed, Cochrane, and Embase to assess randomized controlled trials (RCTs) published up to November 2023 to retrieve studies that measured the parameters before and after the administration of BASs. The outcomes assessed were cessation or improvement in diarrhea, fecal consistency, abdominal cramping, frequency of diarrhea, and adverse events. Risk ratios (RRs) and mean differences with 95% confidence intervals (CIs) were pooled using a random-effects model. Statistical analyses were conducted using RStudio version 4.1.2. The protocol was prospectively registered with PROSPERO (CRD42023445444). Seven RCTs with a total of 311 patients were included, of which 168 (54%) were randomized to BASs. Among BAS-treated patients, 101 (60.1%) received colesevelam, 40 (23.8%) received chenodeoxycholate, 18 (10.7%) received cholestyramine, and 9 (5.3%) received colestid. BASs were associated with a significant improvement in the cessation of diarrhea (RR 3.27; 95% CI 2.08 to 5.15; P ≤ .05) and liquid stool to normal fecal consistency (RR 2.69; 95% CI 1.56 to 4.65; P ≤ .05), as well as an increase in abdominal cramps (RR 5.27; 95% CI 1.21 to 22.93; P ≤ .05). There were no differences in urgency, adverse events, or nausea between groups. These findings indicate that BASs are effective in the treatment of BAD, as indicated by the improvement or cessation of diarrhea episodes.

The Effect of Colesevelam on the Microbiome in Postoperative Crohn's Disease.

While surgery plays a pivotal role in the management of ileal Crohn's disease, the risk of endoscopic recurrence following an ileocaecal resection can be greater than 65% within 12 months of surgery. More than 90% of patients with Crohn's disease have a concomitant diagnosis of bile acid diarrhea following an ileal resection. This pilot study aimed to assess whether the use of bile acid sequestrants in patients with Crohn's disease who have undergone a primary terminal ileal resection with concomitant bile acid diarrhea can alter the microbiome and prevent disease recurrence. Patients with Crohn's disease who underwent a primary terminal ileal resection and had symptoms of diarrhea within 1-3 months of surgery underwent 75SeHCAT testing for bile acid diarrhea. If positive (75SeHCAT ≤ 15%), patients were treated with colesevelam and stool samples were collected at 4 weeks, 8 weeks, and 6-12 months posttreatment. If negative (75SeHCAT > 15%), treatment was not given and were reviewed in the clinic as per local guidelines. All patients underwent a 6-12 month postoperative colonoscopy where further stool samples and mucosal biopsies were taken. Disease activity was established using the endoscopic Rutgeert's score, with disease remission defined as Rutgeert's score <i2 and disease recurrence ≥i2. 16S ribosomal RNA gene analysis was undertaken for the collected fecal and mucosal samples to assess α/β-diversity and microbial composition. A total of 14 patients who completed the study, 10 of whom had a 75SeHCAT positive diagnosis of bile acid diarrhea and were started on treatment with colesevelam. Four patients did not require treatment as 3 were asymptomatic and 1 had a negative 75SeHCAT scan. Three of the fourteen patients had disease recurrence at their 6-12 month postoperative colonoscopy assessment, of which 1 patient was taking colesevelam and 2 patients were not taking colesevelam. A total of 44 fecal samples and 44 mucosal biopsies underwent 16S ribosomal RNA gene analysis to assess α/β-diversity and microbial composition. In the colesevelam treated patients there was no significant difference in α/β-diversity pre- and posttreatment. Pretreatment, the 3 most abundant bacterial classes in all patients were Bacteroidia, Clostridia, and Gammaproteobacteria. Following 6-12 months of treatment, out of the 9 patients on colesevelam, 5/9 (55.6%) had a reduction in Bacteroidia, 9/9 (100%) had an increase in Clostridia, and 7/9 (77.8%) had a reduction in Gammaproteobacteria. Of the 2 patients not given colesevelam, one showed a reduction in Bacteroidia, increase in Clostridia and a reduction in Gammaproteobacteria. This small pilot study demonstrated that patients who were given colesevelam, were more likely to be in disease remission at their 6-12 months colonoscopy review compared with those not treated. Furthermore, treatment with colesevelam may have a role in altering the microbiome to help maintain remission states in postoperative Crohn's disease. Larger mechanistic studies are now needed to confirm these findings and demonstrate statistical significance as well as investigate whether this benefit may be present even in those patients with 75SeHCAT negative disease.

Use of cholesterol-lowering medications in relation to risk of primary liver cancer in the Clinical Practice Research Datalink.

Although the relation between statin use and liver cancer risk has been extensively examined, few studies have examined other cholesterol-lowering medications in relation to liver cancer risk. The authors examined five classes of nonstatin medications and liver cancer risk. A nested case-control including 3719 cases and 14,876 matched controls was conducted within the Clinical Practice Research Datalink. Additional matches on type 2 diabetes and chronic liver disease were also implemented. The medications examined included cholesterol absorption inhibitors, bile acid sequestrants, fibrates, niacin, and omega-3 fatty acids. Conditional logistic regression estimated odds ratios and 95% confidence intervals. Cholesterol absorption inhibitor use was associated with reduced liver cancer risk in the overall analysis (odds ratio, 0.69; 95% confidence interval, 0.50-0.96) and in analyses based on type 2 diabetes and chronic liver disease status. Although bile acid sequestrant use was associated with increased liver cancer risk in the overall analysis (odds ratio, 5.31; 95% confidence interval, 3.53-7.97), the results of the analyses based on type 2 diabetes and chronic liver disease status were inconsistent. [Correction added on 19 August 2024, after first online publication: In the preceding sentence, the value '3.534' has been changed to '3.54'.]. No associations were observed for the other medications. Cholesterol absorption inhibitors may be associated with reduced liver cancer risk. Whether bile acid sequestrant use was associated with increased risk was only partially supported in the current study.

S1233 Comparative Effectiveness of Bile Acid Sequestrants and Antibiotics in the Management of Pouchitis: A Matched Cohort Study From the United States

S1233 Comparative Effectiveness of Bile Acid Sequestrants and Antibiotics in the Management of Pouchitis: A Matched Cohort Study From the United States

Itching for Answers: A Comprehensive Review of Cholestatic Pruritus Treatments

Cholestasis is a clinical and laboratory syndrome indicating impaired bile production or excretion. One of the hallmark symptoms of cholestasis is pruritus. Itch can be severe and debilitating for patients, impacting their quality of life similarly to pain, and, in some cases, it can be refractory. Current therapies like anion exchange resins and rifampicin, offer partial relief but with side effects. Effective, well-tolerated treatments are urgently needed. This literature review examines existing options (bile acid sequestrants, antihistamines, opioid antagonists, sertraline, and rifampicin) and explores novel therapies (monoclonal antibodies, PPAR agonists, and bile-acid-based therapies). We analyze mechanisms, limitations, and adverse effects to aid clinicians and researchers. Novel approaches include monoclonal antibodies to inhibit bile recirculation and PPAR agonists targeting pruritus signaling. Despite the limited current options, ongoing research promises better treatments for cholestatic pruritus, addressing its distressing impact. In summary, cholestasis-associated pruritus poses a significant challenge with limited treatments. Advancements in understanding its pathophysiology offer hope for more effective therapies in the future.

Microscopic Colitis: An Underestimated Disease of Growing Importance

The aim of this paper is to raise awareness of MC as a clinically significant condition and to highlight its under-recognition, risk factors, diagnosis, management, and complications. This paper underlines the diagnostic and therapeutic challenges associated with the often nonspecific symptoms of MC. In order to create this article, we reviewed available articles found in the PubMed database and searched for articles using the Google Scholar platform. Microscopic colitis (MC) is a chronic inflammatory bowel disease, classified into three types: lymphocytic, collagenous, and unspecified. The average age of onset of MC is around 62–65 years and the disease is more common in women than men (nine times more common). The main symptom of MC is watery diarrhoea without blood, other symptoms include defecatory urgency, faecal incontinence, abdominal pain, nocturnal bowel movements, and weight loss. Once considered a rare disease, MC is now being diagnosed with increasing frequency, but diagnosis remains difficult. To date, a number of causative factors for MC have been identified, including smoking, alcohol consumption, medications (including NSAIDs, PPIs, SSRIs, and ICPIs), genetic factors, autoimmune diseases, bile acid malabsorption, obesity, appendicitis, and intestinal dysbiosis. It may be difficult to recognize and should be differentiated from inflammatory bowel diseases (Crohn’s disease and ulcerative colitis), irritable bowel syndrome (IBS), coeliac disease, infectious bowel disease, and others. Diagnosis involves biopsy at colonoscopy and histopathological evaluation of the samples. Treatment consists of budesonide oral (the gold standard) or enema. Alternatives include bile acid sequestrants (cholestyramine, colesevelam, and colestipol), biologics (infliximab, adalimumab, and vedolizumab), thiopurines, methotrexate, and rarely, surgery.

Reversal of hepatic accumulation of nordeoxycholic acid underlines the beneficial effects of cholestyramine on alcohol-associated liver disease in mice.

Dysregulation of bile acids (BAs) has been reported in alcohol-associated liver disease. However, the causal relationship between BA dyshomeostasis and alcohol-associated liver disease remains unclear. The study aimed to determine whether correcting BA perturbation protects against alcohol-associated liver disease and elucidate the underlying mechanism. BA sequestrant cholestyramine (CTM) was administered to C57BL/6J mice fed alcohol for 8 weeks to assess its protective effect and explore potential BA targets. The causal relationship between identified BA metabolite and cellular damage was examined in hepatocytes, with further manipulation of the detoxifying enzyme cytochrome p450 3A11. The toxicity of the BA metabolite was further validated in mice in an acute study. We found that CTM effectively reversed hepatic BA accumulation, leading to a reversal of alcohol-induced hepatic inflammation, cell death, endoplasmic reticulum stress, and autophagy dysfunction. Specifically, nordeoxycholic acid (NorDCA), a hydrophobic BA metabolite, was identified as predominantly upregulated by alcohol and reduced by CTM. Hepatic cytochrome p450 3A11 expression was in parallel with NorDCA levels, being upregulated by alcohol and reduced by CTM. Moreover, CTM reversed alcohol-induced gut barrier disruption and endotoxin translocation. Mechanistically, NorDCA was implicated in causing endoplasmic reticulum stress, suppressing autophagy flux, and inducing cell injury, and such deleterious effects could be mitigated by cytochrome p450 3A11 overexpression. Acute NorDCA administration in mice significantly induced hepatic inflammation and injury along with disrupting gut barrier integrity, leading to subsequent endotoxemia. Our study demonstrated that CTM treatment effectively reversed alcohol-induced liver injury in mice. The beneficial effects of BA sequestrant involve lowering toxic NorDCA levels. NorDCA not only worsens hepatic endoplasmic reticulum stress and inhibits autophagy but also mediates gut barrier disruption and systemic translocation of pathogen-associated molecular patterns in mice.

Lipid-Lowering Medications for Managing Dyslipidemia: A Narrative Review.

Dyslipidemia refers to the change in the normal levels of one or more lipid components in the bloodstream, which include triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C). Dyslipidemia represents a substantial source of danger for cardiovascular disease (CVD). Effectively managing dyslipidemia involves a thorough strategy that includes changing one's lifestyle and using medications that are specifically designed to target the complex processes involved in lipid metabolism. Lipid-lowering treatments play a crucial role in this approach, providing a wide range of medications that are developed to specifically target different components of dyslipidemia. Statins are the main drug among these medications. Other drugs that are used with statin or as monotherapy include fibrates, omega-3 fatty acids (OM3FAs), ezetimibe, bile acid sequestrants, proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, and bempedoic acid. Using the PubMed database, we reviewed the literature about dyslipidemia, drugs used for treating dyslipidemia, their efficacy parameters, and common adverse events. We also reviewed the international guidelines for treating dyslipidemia and discussed the future of lipid-lowering medications. More trials and experiments are still required to verify the effectiveness of many lipid-lowering drugs and to know their common adverse events to be able to manage them properly.

Effectiveness of Bile Acid Sequestrants in Microscopic Colitis and Utility of Bile Acid Testing: A Systematic Review and Meta-analysis.

Bile acid sequestrants (BAS) are an option for microscopic colitis (MC) refractory or intolerant to budesonide. There are inconsistent data on the prevalence of bile acid malabsorption (BAM) and utility of bile acid testing in MC. The aim of this systematic review and meta-analysis was to evaluate these outcomes. A systematic search of randomized control trials and observational studies of adults with MC treated with BAS was conducted using MEDLINE, Embase, Cochrane, and Scopus from inception to January 22, 2024. Data were extracted on (i) prevalence of BAM, (ii) clinical response and adverse events, and (iii) recurrence after BAS discontinuation. Data were pooled using random-effects models to determine weighted pooled estimates and 95% confidence intervals (CIs). We included 23 studies (1 randomized control trial, 22 observational), with 1,011 patients with MC assessed for BAM and 771 treated with BAS. The pooled prevalence of BAM was 34% (95% CI 0.26-0.42, I2 = 81%). The pooled response rate with BAS induction for all patients with MC, irrespective of BAM, was 62% (95% CI 0.55-0.70, I2 = 71%). There was a higher pooled response rate in patients with BAM compared with those without BAM ( P < 0.0001). The pooled rate of BAS-related adverse effects was 9% (95% CI 0.05-0.14, I2 = 58%). One-third of patients with MC had BAM, and almost two-thirds of all patients responded to BAS with limited side effects. Patients with MC and BAM were more likely to respond to therapy, supporting the value of bile acid testing.

Recent Advances in the Treatment of Irritable Bowel Syndrome: Addressing Diarrhea, Constipation, and Abdominal Pain

Irritable bowel syndrome (IBS) is a prevalent gastrointestinal disorder characterized by abdominal pain, bloating, and changes in bowel habits. This paper aim was to provide an overview of recent advancements in the treatment of IBS, focusing on the management of its main symptoms: diarrhea, constipation, and abdominal pain. For individuals with IBS-D, various therapeutic options are available, including rifaximin, peripheral opioid agonists, mixed opioid agonists/antagonists, bile acid sequestrants, and serotonin 5-HT3 receptor antagonists. Rifaximin, a nonabsorbable antibiotic, has demonstrated significant effectiveness in reducing IBS symptoms, such as bloating and loose stools, with good tolerability and safety. Also the repeated use of rifaximin for managing recurrent IBS symptoms. In IBS-C patients, bulking agents, osmotic laxatives, and prokinetic agents like lubiprostone have shown efficacy in improving constipation and overall symptoms. Linaclotide, a drug that increases intestinal chloride secretion, has demonstrated significant improvement in bowel movements and abdominal pain in IBS-C patients. However, it may cause diarrhea in some individuals. IBS-M, characterized by alternating constipation and diarrhea, poses a challenge in terms of specific drug treatments. A comprehensive assessment of potential underlying causes and careful history taking is crucial for effective management. Abdominal pain is a common symptom in IBS, regardless of subtype. Antispasmodic drugs, peppermint oil, and trimebutine have shown effectiveness in reducing pain and improving symptoms. Antidepressants, such as tricyclic antidepressants and selective serotonin reuptake inhibitors, may offer relief by modulating pain pathways and influencing gastrointestinal motility. Benzodiazepines, particularly dextofisopam, have shown potential in improving stool consistency but require further evaluation. In conclusion, recent advancements in the treatment of IBS have provided a range of therapeutic options targeting its main symptoms. However, further research is needed to develop tailored treatments for specific IBS subtypes and to explore the efficacy of potential alternatives, including benzodiazepines. Improved management of IBS symptoms can significantly enhance the quality of life for affected individuals.

#1212 Trends in real-world lipid lowering therapy use among adult patients with chronic kidney disease: 5-year single center experience in the Philippines

Abstract Background and Aims Patients with chronic kidney disease (CKD) carry an extremely high burden for atherosclerotic cardiovascular disease (ASCVD), which worsens as CKD progresses. Several international guidelines, including the 2013 Kidney Disease: Improving Global Outcomes (KDIGO) guidelines, have recommended the use of lipid-lowering therapy (LLT) in this high-risk population. To evaluate the implementation of these recommendations in real-world practice, we assessed patterns of dyslipidemia management among patients with CKD. Specific objectives include describing the prevalence and intensity of LLT prescription [stratified by estimated glomerular filtration rate (GFR) and whether requiring renal replacement therapy or not] as well as adherence to guideline recommendations on LLT use. Method We conducted a single-center, cross-sectional study covering the period of January 2019 to December 2023. A review of inpatient and outpatient medical records of the Department of Medicine, University of the Philippine—Philippine General Hospital was done. Eligible patients were at least 18 years of age, and diagnosed with CKD. Exclusion criteria included having a concomitant diagnosis of Acute Kidney Injury, and being pregnant or breastfeeding at any point in the study period. Sociodemographic, clinical, and laboratory data were based off the latest entry in each patient's medical record. No clinical data were collected beyond those that were available on the records. Classification of statin intensity was based on the 2019 American Heart Association/American College of Cardiology Guidelines on the Management of Blood Cholesterol as well as the 2020 Philippine Clinical Practice Guidelines on the Management of Dyslipidemia. All analyses were descriptive and done using STATA 18. Categorical variables were summarized as frequencies and percentages. Continuous variables were reported as measures of central tendency [i.e. mean (SD) or median (IQR), as appropriate]. Results Of the 3845 patients included in the study, 2922 (76%) were prescribed LLT. The most common LLT were statins (92%), followed by statin/ezetimibe combinations (6%), then statin/fibrate combinations (2%). None were prescribed PCKS9 inhibitors, niacin, omega-3 fatty acids, or bile acid sequestrants. Among non-dialytic patients, the distribution of LLT use was as follows: a) eGFR ≥ 60 ml/min/1.73 m2: 40% (173/431) b) eGFR 30-60 ml/min/1.73 m2: 76% (1198/1576) c) eGFR &amp;lt;30 ml/min/1.73 m2: 84% (1551/1838). Among dialytic patients, 68% (601/884) were already on LLT prior to initiation of dialysis while 35% (283/884) were started on LLT after dialysis initiation. Notably, 89% (786/884) of these dialytic patients were still on moderate-to-high-intensity statin doses. Based on recommendations from the 2013 KDIGO guidelines, only 78% (2610/3334) of eligible patients were prescribed on LLT, while 61% (312/511) of ineligible patients were prescribed on LLT. Similar rates of adherence were seen to other international guideline recommendations on the management of dyslipidemia in CKD (e.g. 2018 American Heart Association/American College of Cardiology Guideline on the Management of Blood Cholesterol, 2019 European Society of Cardiology/European Atherosclerosis Society guidelines for the management of dyslipidaemias, 2020 Clinical Practice Guidelines for the management of dyslipidemia in the Philippines). Conclusion Real-world LLT use among CKD patients remains high, even at lower eGFRs. More importantly, a large proportion of patients remain under- and over-treated, highlighting significant gaps between guideline recommendations and real-world clinical practice. Further investigation regarding the underlying reasons for these practice variations is necessary to improve quality of care, and safely reduce the burden of dyslipidemia and ASCVD among CKD patients.

Bile Acid Diarrhea Is Associated With an Increased Incidence of Gastrointestinal Cancers.

Bile acid diarrhea (BAD) is an underrecognized and socially debilitating disease caused by high concentrations of bile acids in the colon. Bile acids directly and indirectly promote carcinogenesis. In this article, we investigated whether individuals with BAD have an increased risk of gastrointestinal (GI) cancers. By using the Danish health registries, adult individuals with BAD were identified by International Classification of Diseases 10th revision code K90.8 or referral to the diagnostic ⁷⁵selenium-homotaurocholic acid test followed by prescription of a bile acid sequestrant within 365 days (n = 5,245). Age- and sex-matched individuals without BAD were included for comparison (n = 52,450). We analyzed the cumulative incidence of GI cancers after BAD diagnosis and the odds ratios (ORs) of GI cancer 8 and 15 years before BAD diagnosis/matching. Cumulative incidence of GI cancer 6 years after BAD diagnosis/matching was 1.6% in the BAD group and 1.1% in controls ( P = 0.01). The ORs of total GI cancer 8 and 15 years before BAD diagnosis were 6.16 (5.08-7.48) and 5.19 (4.28-6.29), respectively. Furthermore, 47 individuals with BAD (0.9%) and 250 (0.5%) controls died of GI cancer. This nationwide cohort study indicates an association between BAD and GI cancers. We found both a higher incidence of GI cancer after BAD diagnosis compared with controls and increased OR of GI cancer before BAD diagnosis. Bearing in mind the underdiagnosis of BAD, the delay of BAD diagnosis, and the carcinogenic effect of bile acids, these findings warrant further investigations of the risk of GI cancer in individuals with BAD.

Alteration of the bile acid pool attenuates neuroinflammation in the EAE mouse model of Multiple Sclerosis

Bile acids are critical signaling molecules that mediate gut crosstalk with other organs, including the brain. The primary bile acids, such as chenodeoxycholic acid (CDCA), are synthesized in the liver and modified by gut bacteria to generate secondary bile acids like the 12α-hydroxylated deoxycholic acid (DCA). Bile acids are effciently absorbed in the distal ileum, and recent studies have implicated them in neuroinflammation and the pathophysiology of several neurological diseases such as Multiple Sclerosis (MS). However, the specific effects of different types of bile acids on MS have not been thoroughly investigated. We hypothesize that bile acids differentially affect neuroinflammation and that treatment with cholestyramine (bile acid sequestrant) modulates astrocyte activation in a mouse model of MS. Methods: Primary astrocyte cultures were prepared from 6-10-week-old C57BL/6 mice and incubated with cytokines in the presence and absence of bile acids. The expression of inflammatory and astrocyte activation markers was assessed by real-time qPCR. The effects of blocking bile acid absorption on MS were examined using the established Experimental Autoimmune Encephalomyelitis (EAE) mouse model of MS in 8-week-old female mice (C57BL/6). Mice were fed either a standard chow diet or a standard chow diet supplemented with 2% cholestyramine, a bile acid sequestrant, to block bile acid absorption. Statistical significance between groups was determined by an unpaired T-test. Results: Astrocytes treated with cytokines (TNF-α, 10 ng/mL, IL1-β, 10 ng/mL, 24 h) significantly increased the mRNA expression of TNF-α and IL1-β and markers of astrocyte activation, lipocalin 2 (LCN2), and Serpina3n. Co-treatment with cytokines and CDCA but not DCA (50 μM, 24 h) significantly decreased TNF-α (~56%, p&lt;0.01), IL1-β (~40%, p&lt;0.01), LCN2 (~26%, p&lt;.001), and Serpina3n (~44%, p&lt;.001), vs cytokines alone. The taurine-conjugate, TCDCA, also resulted in significant decreases in the expression of TNF-α (~72%, p&lt;0.001), IL1-β (~53%, p&lt;.001), LCN2 (~30%, p&lt;0.05), and Serpina3n (~16%, p&lt;0.01), suggesting an anti-inflammatory effect specific to CDCA and its taurine conjugate on astrocytes. Cholestyramine treatment in EAE mice was associated with significant reductions in the mRNA expression of TNF-α (~40%, p&lt;0.05) and Serpina3n (~30%, p= 0.217) in the frontal cortex of the brain. Together, these data imply that altering the composition of the bile acid pool may be a viable therapeutic strategy for MS patients by attenuating neuroinflammation. University of Illinois at Chicago, JBVMC, Chicago, IL. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Increased intestinal bile acid absorption contributes to age-related cognitive impairment

Cognitive impairment in the elderly is associated with alterations in bile acid (BA) metabolism. In this study, we observe elevated levels of serum conjugated primary bile acids (CPBAs) and ammonia in elderly individuals, mild cognitive impairment, Alzheimer's disease, and aging rodents, with a more pronounced change in females. These changes are correlated with increased expression of the ileal apical sodium-bile acid transporter (ASBT), hippocampal synapse loss, and elevated brain CPBA and ammonia levels in rodents. Invitro experiments confirm that a CPBA, taurocholic acid, and ammonia induced synaptic loss. Manipulating intestinal BA transport using ASBT activators or inhibitors demonstrates the impact on brain CPBA and ammonia levels as well as cognitive decline in rodents. Additionally, administration of an intestinal BA sequestrant, cholestyramine, alleviates cognitive impairment, normalizing CPBAs and ammonia in aging mice. These findings highlight the potential of targeting intestinal BA absorption as a therapeutic strategy for age-related cognitive impairment.

Dyslipidaemia management in pregnant patients: a 2024 update.

Over several decades, the approach to treating dyslipidaemias during pregnancy remains essentially unchanged. The lack of advancement in this field is mostly related to the fact that we lack clinical trials of pregnant patients both with available as well as new therapies. While there are numerous novel therapies developed for non-pregnant patients, there are still many limitations in dyslipidaemia treatment during pregnancy. Besides pharmacotherapy and careful clinical assessment, the initiation of behavioural modifications as well as pre-conception management is very important. Among the various lipid-lowering medications, bile acid sequestrants are the only ones officially approved for treating dyslipidaemia in pregnancy. Ezetimibe and fenofibrate can be considered if their benefits outweigh potential risks. Statins are still considered contraindicated, primarily due to animal studies and human case reports. However, recent systematic reviews and meta-analyses as well as data on familial hypercholesterolaemia (FH) in pregnant patients have indicated that their use may not be harmful and could even be beneficial in certain selected cases. This is especially relevant for pregnant patients at very high cardiovascular risk, such as those who have already experienced an acute cardiovascular event or have homozygous or severe forms of heterozygous FH. In these cases, the decision to continue therapy during pregnancy should weigh the potential risks of discontinuation. Bempedoic acid, olezarsen, evinacumab, evolocumab and alirocumab, and inclisiran are options to consider just before and after pregnancy is completed. In conclusion, decisions regarding lipid-lowering therapy for pregnant patients should be personalized. Despite the challenges in designing and conducting studies in pregnant women, there is a strong need to establish the safety and efficacy of dyslipidaemia treatment during pregnancy.

Bile Acid Diarrhea

Diarrhea is a very common gastrointestinal symptom, and the presence of higher concentrations of bile acid in the colon leads to bile acid diarrhea (BAD). In BAD patients, a portion of bile from the small intestine that is normally controlled by enterohepatic circulation is present at a high concentration in the lumen of the large intestine, resulting in increased motility and secretion of the large intestine. The prevalence of BAD is estimated to be 1-2% of the general population, and it comprises one-third of the instances of diarrhea-predominant irritable bowel syndrome. The clinical symptoms of BAD include chronic diarrhea, increased frequency of defecation, urgency to defecate, fecal incontinence, and cramping abdominal pain. The pathophysiology of BAD has not yet been fully elucidated. However, recent studies have reported increased intestinal permeability, shortened intestinal transit time, and changes in the intestinal microbial community to be the possible causes of BAD. Although fecal and serum bile acid tests are widely used for diagnosis, new test methods that are non-invasive, inexpensive, and have high sensitivity and specificity are needed at various institutions to facilitate the diagnosis. The selenium homo-tauro-cholic acid (SeHCAT) test is the gold standard for BAD diagnosis and severity assessment. The validation of several other serum markers, such as 7-hydroxy-4-cholesten-3-one (serum 7αC4) and the fibroblast growth factor 19 (FGF19) for use in clinical practice is ongoing. Although bile acid sequestrants are the mainstay of treatment, the development of drugs that are more effective and have better compliance is required. Farnesoid X receptor (FXR) agonists are showing promising results.

Short-term treatment with cholestyramine increases long-acting anticoagulant rodenticide clearance from rabbits without affecting plasma vitamin K1 levels or blood coagulation.

Administration of high-dose vitamin K1 (VK1) overcomes coagulopathy and bleeding elicited by acute poisoning with long-acting anticoagulant rodenticides (LAARs). However, long-term (months) treatment is required due to long LAAR biological half-lives that may lead to poor compliance and recurrent coagulopathy. The half-lives of LAARs are extended by slow metabolism, and similar to warfarin, are thought to undergo enterohepatic recirculation. We now show that treatment with the bile acid sequestrant cholestyramine (CSA) administered concomitantly with VK1 decreases plasma LAAR levels and increases LAAR fecal excretion. Daily CSA treatment for 14 days did not reduce plasma VK1 levels, or increase prothrombin time. Collectively, these data show that CSA accelerates LAAR clearance from rabbits without adverse effects on VK1 anticoagulation, and could provide an additional therapeutic option for treatment of LAAR poisoning.

First Iranian guidelines for the diagnosis, management, and treatment of hyperlipidemia in adults.

This guideline is the first Iranian guideline developed for the diagnosis, management, and treatment of hyperlipidemia in adults. The members of the guideline developing group (GDG) selected 9 relevant clinical questions and provided recommendations or suggestions to answer them based on the latest scientific evidence. Recommendations include the low-density lipoprotein cholesterol (LDL-C) threshold for starting drug treatment in adults lacking comorbidities was determined to be over 190 mg/dL and the triglyceride (TG) threshold had to be >500 mg/dl. In addition to perform fasting lipid profile tests at the beginning and continuation of treatment, while it was suggested to perform cardiovascular diseases (CVDs) risk assessment using valid Iranian models. Some recommendations were also provided on lifestyle modification as the first therapeutic intervention. Statins were recommended as the first line of drug treatment to reduce LDL-C, and if its level was high despite the maximum allowed or maximum tolerated drug treatment, combined treatment with ezetimibe, proprotein convertase subtilisin/kexin type 9 inhibitors, or bile acid sequestrants was suggested. In adults with hypertriglyceridemia, pharmacotherapy with statin or fibrate was recommended. The target of drug therapy in adults with increased LDL-C without comorbidities and risk factors was considered an LDL-C level of <130 mg/dl, and in adults with increased TG without comorbidities and risk factors, TG levels of <200 mg/dl. In this guideline, specific recommendations and suggestions were provided for the subgroups of the general population, such as those with CVD, stroke, diabetes, chronic kidney disease, elderly, and women.

Journal of Clinical Gastroenterology Lectureship Dubai 2022 : Management of Irritable Bowel Syndrome With Diarrhea.

Irritable bowel syndrome (IBS) with diarrhea (IBS-D) affects ~1% of the general population and is characterized by abdominal pain associated with diarrhea. IBS-D symptoms significantly impact the quality of life of patients. Major uncertainties remain regarding the optimal management of these patients. Several therapies have been investigated over the years for the treatment of IBS-D. In the initial management, commonly prescribed approaches with an effect on global IBS symptoms include a low Fermentable Oligo-, Di-, Mono-Saccharides and Polyols diet and probiotics, while antispasmodics are used for targeting abdominal pain and loperamide for diarrhea only. Additional therapeutic options for the relief of global IBS symptoms include rifaximin, 5-HT 3 antagonists, gut-directed psychological therapies, and eluxadoline, while tricyclic antidepressants can target abdominal pain and bile acid sequestrants diarrhea. Promising evidence exists for the use of mesalazine and fecal microbiota transplantation in IBS-D, although further evidence is needed for definitive conclusions regarding their efficacy.