Best Practices for Development and Validation of Enzymatic Activity Assays to Support Drug Development for Inborn Errors of Metabolism and Biomarker Assessment.

Aberrant or dysfunctional cellular enzymes are responsible for a wide range of diseases including cancer, neurodegenerative conditions, and metabolic disorders. Deficiencies in enzyme level or biofunction may lead to intracellular accumulation of substrate to toxic levels and interfere with overall cellular function, ultimately leading to cell damage, disease, and death. Marketed therapeutic interventions for inherited monogenic enzyme deficiency disorders include enzyme replacement therapy and small molecule chaperones. Novel approaches of in vivo gene therapy and ex vivo cell therapy are under clinical evaluation and provide promising opportunities to expand the number of available disease-modifying treatments. To support the development of these different therapeutics, assays to quantify the functional activity of protein enzymes have gained importance in the diagnosis of disease, assessment of pharmacokinetics and pharmacodynamic response, and evaluation of drug efficacy. In this review, we discuss the technical aspects of enzyme activity assays in the bioanalytical context, including assay design and format as well as the unique challenges and considerations associated with assay development, validation, and life cycle management.

The adiponectin-derived peptide ALY688 protects against the development of metabolic dysfunction-associated steatohepatitis.

Metabolic dysfunction-associated steatohepatitis (MASH) is the severe form of non-alcoholic fatty liver disease which has a high potential to progress to cirrhosis and hepatocellular carcinoma, yet adequate effective therapies are lacking. Hypoadiponectinemia is causally involved in the pathogenesis of MASH. This study investigated the pharmacological effects of adiponectin replacement therapy with the adiponectin-derived peptide ALY688 (ALY688-SR) in a mouse model of MASH. Human induced pluripotent stem (iPS) cell-derived hepatocytes were used to test cytotoxicity and signaling of unmodified ALY688 in vitro. High-fat diet with low methionine and no added choline (CDAHF) was used to induce MASH and test the effects of ALY688-SR in vivo. Histological MASH activity score (NAS) and fibrosis score were determined to assess the effect of ALY688-SR. Transcriptional characterization of mice through RNA sequencing was performed to indicate potential molecular mechanisms involved. In cultured hepatocytes, ALY688 efficiently induced adiponectin-like signaling, including the AMP-activated protein kinase and p38 mitogen-activated protein kinase pathways, and did not elicit cytotoxicity. Administration of ALY688-SR in mice did not influence body weight but significantly ameliorated CDAHF-induced hepatic steatosis, inflammation, and fibrosis, therefore effectively preventing the development and progression of MASH. Mechanistically, ALY688-SR treatment markedly induced hepatic expression of genes involved in fatty acid oxidation, whereas it significantly suppressed the expression of pro-inflammatory and pro-fibrotic genes as demonstrated by transcriptomic analysis. ALY688-SR may represent an effective approach in MASH treatment. Its mode of action involves inhibition of hepatic steatosis, inflammation, and fibrosis, possibly via canonical adiponectin-mediated signaling.

Advances in Immune Tolerance Induction in Enzyme Replacement Therapy.

Inborn errors of metabolism (IEMs) are a group of genetic diseases that occur due to the either deficiency of an enzyme involved in a metabolic/biochemical pathway or other disturbances in the metabolic pathway including transport protein or activator protein deficiencies, cofactor deficiencies, organelle biogenesis, maturation or trafficking problems. These disorders are collectively significant due to their substantial impact on both the well-being and survival of affected individuals. In the quest for effective treatments, enzyme replacement therapy (ERT) has emerged as a viable strategy for patients with many of the lysosomal storage disorders (LSD) and enzyme substitution therapy in the rare form of the other inborn errors of metabolism including phenylketonuria and hypophosphatasia. However, a major challenge associated with enzyme infusion in patients with these disorders, mainly LSD, is the development of high antibody titres. Strategies focusing on immunomodulation have shown promise in inducing immune tolerance to ERT, leading to improved overall survival rates. The implementation of immunomodulation concurrent with ERT administration has also resulted in a decreased occurrence of IgG antibody development compared with cases treated solely with ERT. By incorporating the knowledge gained from current approaches and analysing the outcomes of immune tolerance induction (ITI) modalities from clinical and preclinical trials have demonstrated significant improvement in the efficacy of ERT. In this comprehensive review, the progress in ITI modalities is assessed, drawing insights from both clinical and preclinical trials. The focus is on evaluating the advancements in ITI within the context of IEM, specifically addressing LSDs managed through ERT.

Development of medicines for rare diseases and inborn errors of metabolism: Toward novel public-private partnerships.

Medicine development for rare diseases, including inborn errors of metabolism (IEMs) is challenging. Many academic innovations fail to reach the patient, either by stranding in the translational stage or due to suboptimal patient access related to pricing or uncertain effectiveness. Expanding and solidifying the role of the academic in public-private partnerships (PPPs) may present an innovative solution to help overcome these complexities. This narrative review explores the literature on traditional and novel collaborative approaches to medicine development for rare diseases and analyzes examples of PPPs, with a specific focus on IEMs. Several academic institutions have introduced guidelines for socially responsible licensing of innovations for private development. The PPP model offers a more integrative approach toward academic involvement of medicine development. By sharing risks and rewards, failures in the translational stage can be mutually absorbed. If socially responsible terms are not included, however, high pricing can impede patient access. Therefore, we propose a framework for socially responsible PPPs aimed at medicine development for metabolic disorders. This socially responsible PPP framework could stimulate successful and accessible medicine development for IEMs as well as other rare diseases if the establishment of such collaborations includes terms securing joint data ownership and evidence generation, fast access, and socially responsible pricing.

Molecular mechanisms of glucocorticoid resistance.

BACKGROUND: As a powerful anti-inflammatory, immunosuppressive, and antiproliferative drug, glucocorticoid (GC) plays an important role in the treatment of various diseases. However, some patients may experience glucocorticoid resistance (GCR) in clinical, and its molecular mechanism have not been determined. METHODS: The authors performed a review of the literature on GCR focusing on mutations in the NR3C1 gene and impaired glucocorticoid receptor (GR) signalling, using METSTR (2000 through May 2022) to identify original articles and reviews on this topic. The search terms included 'glucocorticoid resistance/insensitive', 'steroid resistance/insensitive', 'NR3C1', and 'glucocorticoid receptor'. RESULTS: Primary GCR is mainly caused by NR3C1 gene mutation, and 31 NR3C1 gene mutations have been reported so far. Secondary GCR is caused by impaired GC signalling pathways, including decreased expression of GR, impaired nuclear translocation of GR, and impaired binding of GR to GC and GR to target genes. However, the current research is more on the expression level of GR, and there are relatively few studies on other mechanisms. In addition, methods for improving GC sensitivity are rarely reported. CONCLUSION: The molecular mechanisms of GCR are complex and may differ in different diseases or different patients. In future studies, when exploring the mechanism of GCR, methods to improve GC sensitivity should also be investigated.

RNA solutions to treat inborn errors of metabolism.

RNA-based therapies are a new, rapidly growing class of drugs that until a few years ago were being used mainly in research in rare diseases. However, the clinical efficacy of recently approved oligonucleotide drugs and the massive success of COVID-19 RNA vaccines has boosted the interest in this type of molecules of both scientists and industry, as wells as of the lay public. RNA drugs are easy to design and cost effective, with greatly improved pharmacokinetic properties thanks to progress in oligonucleotide chemistry over the years. Depending on the type of strategy employed, RNA therapies offer the versatility to replace, supplement, correct, suppress, or eliminate the expression of a targeted gene. Currently, there are more than a dozen RNA-based drugs approved for clinical use, including some for specific inborn errors of metabolism (IEM), and many other in different stages of development. New initiatives in n-of-1 RNA drug development offer new hope for patients with rare diseases and/or ultra-rare mutations. RNA-based therapeutics include antisense oligonucleotides, aptamers, small interfering RNAs, small activating RNAs, microRNAs, lncRNAs and messenger RNAs. Further research and collaborations in the fields of chemistry, biology and medicine will help to overcome major challenges in their delivery to target tissues. Herein, we review the mechanism of action of the different therapeutic approaches using RNA drugs, focusing on those approved or in clinical trials to treat IEM.

Clinical experience with orphan drugs for rare metabolic diseases.

INTRODUCTION: Inborn errors of metabolism are a highly heterogeneous group of orphan diseases. Diet therapy and enzyme and coenzyme replacement are the most frequently used treatment. There are few patients and published studies about inborn errors of metabolism. The main objective of this study was to describe the effectiveness of orphan drugs in inborn errors of metabolism in paediatric patients. MATERIAL AND METHODS: Retrospective descriptive study of 24 months on patients diagnosed with inborn errors of metabolism during childhood and who attended the pharmacy clinic or Day-Care Unit of a 630-bed general hospital. RESULTS: The study included 15 patients with a median age of 17.8 years and were treated with nine different drugs: sapropterin, sodium phenylbutyrate, miglustat, velaglucerase, sebelipase, idursulfase, 5-hydroxytryptophan, succinate, and riboflavin. Seven different inborn errors of metabolism were observed: phenylketonuria, defects of the urea cycle, Gaucher, Nieman-Pick, Hunter's disease, along with acid lipase deficiency, and mitochondrial diseases. Orphan drugs used for the treatment of inborn errors of metabolism accounted for 1.3% of hospital drug costs. Some orphan drugs achieved asymptomatic patients, but others just produced a modest symptomatic improvement. Most patients showed good tolerance to the treatment. CONCLUSIONS: Orphan drugs used in inborn errors of metabolism had an easy to manage toxicity profile, with many disparities in effectiveness. These drugs have a high economic impact. The cost-effectiveness ratio for orphan drugs is a controversial issue due to their high cost and the inconclusive clinical evidence.

A Potential Treatment of Congenital Sodium Diarrhea in Patients With Activating GUCY2C Mutations.

INTRODUCTION: Gain-of-function mutations in guanylyl cyclase C (GCC) result in persistent diarrhea with perinatal onset. We investigated a specific GCC inhibitor, SSP2518, for its potential to treat this disorder. METHODS: We investigated the effect of SSP2518 on GCC-mediated intracellular cyclic guanosine monophosphate (cGMP) levels and on GCC-mediated chloride secretion in intestinal organoids from 3 patients with distinct activating GCC mutations and from controls, with and without stimulation of GCC with heat-stable enterotoxin. RESULTS: Patient-derived organoids had significantly higher basal cGMP levels than control organoids, which were lowered by SSP2518 to levels found in control organoids. In addition, SSP2518 significantly reduced cGMP levels and chloride secretion in patient-derived and control organoids (P < 0.05 for all comparisons) after heat-stable enterotoxin stimulation. DISCUSSION: We reported in this study that the GCC inhibitor SSP2518 normalizes cGMP levels in intestinal organoids derived from patients with GCC gain-of-function mutations and markedly reduces cystic fibrosis transmembrane conductance regulator-dependent chloride secretion, the driver of persistent diarrhea.

Neonatal seizures as onset of Inborn Errors of Metabolism (IEMs): from diagnosis to treatment. A systematic review.

Neonatal seizures (NS) occur in the first 28 days of life; they represent an important emergency that requires a rapid diagnostic work-up to start a prompt therapy. The most common causes of NS include: intraventricular haemorrhage, hypoxic-ischemic encephalopathy, hypoglycemia, electrolyte imbalance, neonatal stroke or central nervous system infection. Nevertheless, an Inborn Error of Metabolism (IEM) should be suspected in case of NS especially if these are resistant to common antiseizure drugs (ASDs) and with metabolic decompensation. Nowadays, Expanded Newborn Screening (ENS) has changed the natural history of some IEMs allowing a rapid diagnosis and a prompt onset of specific therapy; nevertheless, not all IEMs are detected by such screening (e.g. Molybdenum-Cofactor Deficiency, Hypophosphatasia, GLUT1-Deficiency Syndrome) and for this reason neonatologists have to screen for these diseases in the diagnostic work-up of NS. For IEMs, there are not specific semiology of seizures and EEG patterns. Herein, we report a systematic review on those IEMs that lead to NS and epilepsy in the neonatal period, studying only those IEMs not included in the ENS with tandem mass, suggesting clinical, biochemical features, and diagnostic work-up. Remarkably, we have observed a worse neurological outcome in infants undergoing only a treatment with common AED for their seizures, in comparison to those primarily treated with specific anti-convulsant treatment for the underlying metabolic disease (e.g.Ketogenic Diet, B6 vitamin). For this reason, we underline the importance of an early diagnosis in order to promptly intervene with a targeted treatment without waiting for drug resistance to arise.

A review of treatment modalities in gyrate atrophy of the choroid and retina (GACR).

Gyrate atrophy of the choroid and retina (GACR) is a rare inborn error of amino acid metabolism caused by bi-allelic variations in OAT. GACR is characterised by vision decline in early life eventually leading to complete blindness, and high plasma ornithine levels. There is no curative treatment for GACR, although several therapeutic modalities aim to slow progression of the disease by targeting different steps within the ornithine pathway. No international treatment protocol is available. We systematically collected all international literature on therapeutic interventions in GACR to provide an overview of published treatment effects. METHODS: Following the PRISMA guidelines, we conducted a systematic review of the English literature until December 22nd 2020. PubMed and Embase databases were searched for studies related to therapeutic interventions in patients with GACR. RESULTS: A total of 33 studies (n = 107 patients) met the inclusion criteria. Most studies were designed as case reports (n = 27) or case series (n = 4). No randomised controlled trials or large cohort studies were found. Treatments applied were protein-restricted diets, pyridoxine supplementation, creatine or creatine precursor supplementation, l-lysine supplementation, and proline supplementation. Protein-restricted diets lowered ornithine levels ranging from 16.0-91.2%. Pyridoxine responsiveness was reported in 30% of included mutations. Lysine supplementation decreased ornithine levels with 21-34%. Quality assessment showed low to moderate quality of the articles. CONCLUSIONS: Based primarily on case reports ornithine levels can be reduced by using a protein restricted diet, pyridoxine supplementation (variation-dependent) and/or lysine supplementation. The lack of pre-defined clinical outcome measures and structural follow-up in all included studies impeded conclusions on clinical effectiveness. Future research should be aimed at 1) Unravelling the OAT biochemical pathway to identify other possible pathologic metabolites besides ornithine, 2) Pre-defining GACR specific clinical outcome measures, and 3) Establishing an international historical cohort.

COXPD9 in an individual from Puerto Rico and literature review.

Defects of mitoribosome assembly with destabilization of mitochondrial ribosomal proteins and subsequent aberrant mitochondrial translation machinery are one of the emerging categories of human mitochondrial disease. Mitochondrial translation deficiency constitutes a growing cause of combined oxidative phosphorylation deficiency and overall causes a set of clinically heterogeneous multi-systemic diseases. We present here the sixth individual with combined oxidative phosphorylation deficiency-9 (COXPD9) secondary to a likely pathogenic homozygous MRPL3 variant c.571A > C; p.(Thr191Pro). MRPL3 encodes a large mitochondrial ribosome subunit protein, impairing the mitochondrial translation and resulting in multisystem disease. Similar to previously reported individuals, this reported female proband presented with psychomotor retardation, sensorineural hearing loss, hypertrophic cardiomyopathy, failure to thrive, and lactic acidosis. Further, she has additional, previously unreported, features including Leigh syndrome, cataracts, hypotonia, scoliosis, myopathy, exercise intolerance, childhood-onset cardiomyopathy, and microcephaly. This subject is the oldest reported individual with COXPD9. This report also summarizes the clinical and molecular data of the previously reported individuals with COXPD9 to describe the full phenotypic spectrum.

An Unusual Course of a 2,8-Dihydroxyadeninuria Crystalline Nephropathy Secondary to Adenine Phosphoribosyltransferase Deficiency.

Adenine phosphoribosyltransferase (APRT) deficiency is a rare disorder caused by an autosomal recessive genetic disease leading to the deposition of 2,8-dihydroxyadenine (2,8-DHA) in the kidney. The disease remains under-recognized, oftentimes diagnosed in late stages of renal insufficiency or a failed kidney allograft with biopsy-proven disease recurrence. Here, we present the case of a 59-year-old middle eastern male patient diagnosed with 2,8-DHA nephropathy after a very unusual presentation, and we show how the initiation of an appropriate therapy slowed down his evolution toward kidney replacement therapies. His disease was found to be secondary to a specific APRT gene variant c.188G>A p (Gly63Asp) also described in 4 other patients, all from middle eastern origins.

ß3-Adrenoreceptors as ROS Balancer in Hematopoietic Stem Cell Transplantation.

In the last decades, the therapeutic potential of hematopoietic stem cell transplantation (HSCT) has acquired a primary role in the management of a broad spectrum of diseases including cancer, hematologic conditions, immune system dysregulations, and inborn errors of metabolism. The different types of HSCT, autologous and allogeneic, include risks of severe complications including acute and chronic graft-versus-host disease (GvHD) complications, hepatic veno-occlusive disease, lung injury, and infections. Despite being a dangerous procedure, it improved patient survival. Hence, its use was extended to treat autoimmune diseases, metabolic disorders, malignant infantile disorders, and hereditary skeletal dysplasia. HSCT is performed to restore or treat various congenital conditions in which immunologic functions are compromised, for instance, by chemo- and radiotherapy, and involves the administration of hematopoietic stem cells (HSCs) in patients with depleted or dysfunctional bone marrow (BM). Since HSCs biology is tightly regulated by oxidative stress (OS), the control of reactive oxygen species (ROS) levels is important to maintain their self-renewal capacity. In quiescent HSCs, low ROS levels are essential for stemness maintenance; however, physiological ROS levels promote HSC proliferation and differentiation. High ROS levels are mainly involved in short-term repopulation, whereas low ROS levels are associated with long-term repopulating ability. In this review, we aim summarize the current state of knowledge about the role of ß3-adrenoreceptors (ß3-ARs) in regulating HSCs redox homeostasis. ß3-ARs play a major role in regulating stromal cell differentiation, and the antagonist SR59230A promotes differentiation of different progenitor cells in hematopoietic tumors, suggesting that ß3-ARs agonism and antagonism could be exploited for clinical benefit.

Targeted Therapies for Metabolic Myopathies Related to Glycogen Storage and Lipid Metabolism: a Systematic Review and Steps Towards a 'Treatabolome'.

BACKGROUND: Metabolic myopathies are a heterogenous group of muscle diseases typically characterized by exercise intolerance, myalgia and progressive muscle weakness. Effective treatments for some of these diseases are available, but while our understanding of the pathogenesis of metabolic myopathies related to glycogen storage, lipid metabolism and ß-oxidation is well established, evidence linking treatments with the precise causative genetic defect is lacking. OBJECTIVE: The objective of this study was to collate all published evidence on pharmacological therapies for the aforementioned metabolic myopathies and link this to the genetic mutation in a format amenable to databasing for further computational use in line with the principles of the "treatabolome" project. METHODS: A systematic literature review was conducted to retrieve all levels of evidence examining the therapeutic efficacy of pharmacological treatments on metabolic myopathies related to glycogen storage and lipid metabolism. A key inclusion criterion was the availability of the genetic variant of the treated patients in order to link treatment outcome with the genetic defect. RESULTS: Of the 1,085 articles initially identified, 268 full-text articles were assessed for eligibility, of which 87 were carried over into the final data extraction. The most studied metabolic myopathies were Pompe disease (45 articles), multiple acyl-CoA dehydrogenase deficiency related to mutations in the ETFDH gene (15 articles) and systemic primary carnitine deficiency (8 articles). The most studied therapeutic management strategies for these diseases were enzyme replacement therapy, riboflavin, and carnitine supplementation, respectively. CONCLUSIONS: This systematic review provides evidence for treatments of metabolic myopathies linked with the genetic defect in a computationally accessible format suitable for databasing in the treatabolome system, which will enable clinicians to acquire evidence on appropriate therapeutic options for their patient at the time of diagnosis.

Treatment efficacy of high-dose creatine supplementation in a child with creatine transporter (SLC6A8) deficiency.

BACKGROUND: Creatine transporter deficiency is an inborn error of metabolism caused by a deficiency in the creatine transporter protein encoded by the SLC6A8 gene. Previous treatment with creatine supplementation, either alone or in combination with creatine precursors (arginine or glycine), has been attempted; the efficacy of therapy, however, remains controversial. METHODS AND RESULTS: To analyze the treatment efficacy of high-dose creatine supplementation on creatine transporter deficiency, we reported a child diagnosed with creatine transporter deficiency, who was treated with a conventional dose of creatine (400 mg/kg/d) for 1 month, then twice the dose (800 mg/kg/d) for 2 months, and finally 3 times the dose (1200 mg/kg/d) for 3 months. The patient tolerated the treatment well and showed improvements in muscle mass and strength when the creatine dose was gradually increased to 1200 mg/kg/d. However, when assessed by proton magnetic resonance spectroscopy (H-MRS), the brain creatine concentration did not increase, and there was no improvement in speech and neurodevelopmental symptoms. CONCLUSION: We conclude that high-dose creatine supplementation (1200 mg/kg/d) alone improved muscular symptoms, but did not improve cognitive symptoms and brain creatine concentration assessed using H-MRS. Therefore, new treatment strategies are required for the management of creatine transporter deficiency.

Long-term Effect of Aromatase Inhibition in Aromatase Excess Syndrome.

CONTEXT: Aromatase excess syndrome (AEXS) is a very rare disorder characterized by prepubertal gynecomastia, bone age acceleration, and early growth arrest. Heterozygote submicroscopic rearrangements within the promotor of CYP19A1 result in overexpression of aromatase and enhanced aromatization of androgens. OBJECTIVE: The objective was to study long-term treatment effects of an aromatase inhibitor. METHODS: Data from 7 boys with AEXS were retrospectively collected. Genetic analysis revealed upstream of CYP19A1 a 165 901 bp deletion in 4 German cousins, a 198 662 bp deletion in 2 Japanese brothers, and a 387 622 bp tandem duplication in a Japanese boy. RESULTS: All boys developed prepubertal gynecomastia, at median 9.0 years of age (range: 7.0-11.0). Height was +1.20 standard deviation score (SDS) (-0.24 to +1.98); predicted adult height was -1.29 SDS (-3.29 to +1.09). Four boys were treated with 1.0 mg of anastrozole daily, while 3 reached adult height untreated. Treatment with anastrozole was stopped after 5.6 years (4.0-6.8). Three treated boys exceeded their prognosis by 2.4, 6.9, and 8.1 cm, while 1 untreated boy fell below the prognosis by 8.6 cm. One treated with a low dose and 2 untreated reached their prognosis. Adult heights were -0.91 SDS with anastrozole (-2.86 to -0.29) and -0.15 SDS without (-2.31 to -0.03). Distance to target height was -0.22 SDS with anastrozole (-1.72 to +0.52) and +0.54 SDS without (+0.23 to +1.30). CONCLUSION: Spontaneous growth in AEXS varied, even in the same family. Our data suggest that early started, long-term inhibition by anastrozole promotes adult height in boys with AEXS.

Antiretroviral treatment leading to secondary trimethylaminuria: Genetic associations and successful management with riboflavin.

WHAT IS KNOWN AND OBJECTIVE: Trimethylaminuria is a metabolic disorder characterized by excessive excretion of trimethylamine in body fluids following FMO3 gene mutations. Secondary forms of the disease may be due to consumption of trimethylamine precursor-rich foods or metabolism of some xenobiotics. CASE SUMMARY: A HIV patient developed secondary trimethylaminuria following antiretroviral treatment. Riboflavin supplementation ameliorated his phenotype. 1 H-NMR confirmed increased urine level of TMA. Several genes involved in choline catabolism harboured missense mutations. Riboflavin supplement improved enzymatic activity of mutated enzymes promoting TMA clearance. WHAT IS NEW AND CONCLUSION: Antiretrovirals may increase the concentration of TMA precursors. The present study reports antiretroviral treatment as risk factor for such secondary trimethylaminuria. Riboflavin is an effective treatment.

High-throughput sequencing analysis of differences in intestinal microflora between ulcerative colitis patients with different glucocorticoid response types.

BACKGROUND: Previous investigations reported that the imbalance of intestinal microflora may be the initiation and promotion factor in the pathogenesis of inflammatory bowel disease such as ulcerative colitis (UC). Glucocorticoid is a very important class of regulatory molecules in the body. The response of different individuals to glucocorticoids can be divided into glucocorticoid sensitive, glucocorticoid resistance and glucocorticoid dependence. OBJECTIVE: We aimed to investigate the differences in intestinal microflora composition and related metabolic pathways in UC patients with these three different glucocorticoid response types. METHODS: The whole genomic DNA was extracted from fecal specimens. High-throughput sequencing technology was used to analyze the fecal 16S rRNA genome of UC patients with different glucocorticoid response types, and functional prediction was performed by PICRUSTs software. RESULTS: The results showed that the intestinal microflora of the three groups were mainly composed of Firmicutes, Proteobacteria and Bacteroidetes. Although the species abundance and diversity of intestinal microflora in UC patients differed little among the three groups, the composition of intestinal microflora showed significant heterogeneity, which directly led to differences in the function of intestinal microbiota of UC patients with different glucocorticoid responses. Furthermore, of the 240 pathways, "PANTO-PWY: phosphopantothenate biosynthesis I", "COA-PWY-1: coenzyme A biosynthesis II (mammalian)" and "PWY-4242: pantothenate and coenzyme A biosynthesis III" were significantly different in the three groups. CONCLUSIONS: These results indicate that UC patients with different glucocorticoids response types have different bacterial compositions and functions, which lays a foundation for further study of glucocorticoid resistance in UC patients.

Glucocorticoid Resistance is Associated with Poor Functional Outcome After Stroke.

Systemic inflammation is associated with poor outcome after stroke. Glucocorticoids (GCs) play a fundamental role in limiting inflammation. The aim of this study was to explore the associations between GC sensitivity, systemic inflammation, and outcome after ischemic stroke. The study population compised 246 ischemic stroke patients (median age: 69.0 years; 41.1% female). To assess GC sensitivity, we incubated venous blood samples that were obtained at day 3 after stroke with lipopolysaccharide (10 ng/mL) and dexamethasone (10-6 mol/L). We defined the GC sensitivity index as the ratio of tumor necrosis factor α (TNFα) released after blood stimulation with lipopolysaccharide and dexamethasone to the amount of TNFα released after blood stimulation with lipopolysaccharide alone. A higher index indicates higher GC resistance. The patients with poor functional outcome had a higher GC sensitivity index than those with good outcome (median: 16.1% vs. 13.5%, P < 0.01). In a logistic regression analysis adjusted for age, stroke severity, pneumonia, leukocyte count, plasma interleukin-6, and TNFα release ex vivo, a higher GC sensitivity index was associated with a higher risk of poor outcome after stroke (OR 2.32, 95% CI 1.21-4.45, P = 0.01). In conclusion, GC resistance is associated with poor functional outcome after stroke.