Recurrent hepatic encephalopathy (HE) is a leading cause of readmission despite standard of care (SOC) associated with microbial dysbiosis. Fecal microbiota transplantation (FMT) may improve dysbiosis; however, it has not been studied in HE. We aimed to define whether FMT using a rationally-derived stool donor is safe in recurrent HE compared to SOC alone. An open-label, randomized clinical trial with a 5 month follow-up in outpatient cirrhotic men with recurrent HE on SOC was conducted with 1:1 randomization. FMT-randomized patients received 5-days of broad-spectrum antibiotic pre-treatment then a single FMT enema from the same donor with the optimal microbiota deficient in HE. Follow-up occurred on days 5, 6, 12, 35 and 150 post-randomization. The primary outcome was safety of FMT compared to SOC using FMT-related serious adverse events (SAE). Secondary outcomes were AEs, cognition, microbiota and metabolomic changes. Participants in both arms were similar on all baseline criteria and were followed till study-end. FMT with antibiotic pre-treatment was well-tolerated. Eight (80%) SOC participants had a total of 11 SAE compared to two (20%) FMT participants with SAEs (both FMT-unrelated, p=0.02). Five SOC and no FMT participants developed further HE (p=0.03). Cognition improved in FMT, but not SOC group. MELD score transiently worsened post-antibiotics, but reverted to baseline post-FMT. Post-antibiotics, beneficial taxa and microbial diversity reduction occurred with Proteobacteria expansion. However, FMT increased diversity and beneficial taxa. SOC microbiota and MELD score remained similar throughout. Conclusions: FMT from a rationally selected donor reduced hospitalizations, improved cognition and dysbiosis in cirrhosis with recurrent HE.
Background: The cardiomyopathies, classically categorized as hypertrophic (HCM), dilated (DCM), and arrhythmogenic right ventricular (ARVC), each have a signature genetic theme. HCM and ARVC are largely understood as genetic diseases of sarcomere or desmosome proteins, respectively. In contrast, >250 genes spanning more than 10 gene ontologies have been implicated in DCM, representing a complex and diverse genetic architecture. To clarify this, a systematic curation of evidence to establish the relationship of genes with DCM was conducted. Methods: An international Panel with clinical and scientific expertise in DCM genetics evaluated evidence supporting monogenic relationships of genes with idiopathic DCM. The Panel utilized the ClinGen semi-quantitative gene-disease clinical validity classification framework with modifications for DCM genetics to classify genes into categories based on the strength of currently available evidence. Representation of DCM genes on clinically available genetic testing panels was evaluated. Results: Fifty-one genes with human genetic evidence were curated. Twelve genes (23%) from eight gene ontologies were classified as having definitive ( BAG3, DES, FLNC, LMNA, MYH7, PLN, RBM20, SCN5A, TNNC1, TNNT2, TTN ) or strong ( DSP ) evidence. Seven genes (14%) ( ACTC1, ACTN2, JPH2, NEXN, TNNI3, TPM1, VCL ) including two additional ontologies were classified as moderate evidence; these genes are likely to emerge as strong or definitive with additional evidence. Of these 19 genes, six were similarly classified for HCM and three for ARVC. Of the remaining 32 genes (63%), 25 (49%) had limited evidence, 4 (8%) were disputed, 2 (4%) had no disease relationship, and 1 (2%) was supported by animal model data only. Of 16 evaluated clinical genetic testing panels, most definitive genes were included, but panels also included numerous genes with minimal human evidence. Conclusions: In the curation of 51 genes, 19 had high evidence (12 definitive/strong; seven moderate). Notably, these 19 genes only explain a minority of cases, leaving the remainder of DCM genetic architecture incompletely addressed. Clinical genetic testing panels include most high evidence genes, however genes lacking robust evidence are also commonly included. We recommend that high evidence DCM genes be used for clinical practice and to exercise caution when interpreting variants in variable evidence DCM genes.
Micronutrient deficiency and depression are major global health problems. Here, we first review recent empirical evidence of the association between several micronutrients—zinc, magnesium, selenium—and depression. We then present potential mechanisms of action and discuss the clinical implications for each micronutrient. Collectively, empirical evidence most strongly supports a positive association between zinc deficiency and the risk of depression and an inverse association between zinc supplementation and depressive symptoms. Less evidence is available regarding the relationship between magnesium and selenium deficiency and depression, and studies have been inconclusive. Potential mechanisms of action involve the HPA axis, glutamate homeostasis and inflammatory pathways. Findings support the importance of adequate consumption of micronutrients in the promotion of mental health, and the most common dietary sources for zinc and other micronutrients are provided. Future research is needed to prospectively investigate the association between micronutrient levels and depression as well as the safety and efficacy of micronutrient supplementation as an adjunct treatment for depression.
Background: Cyclophilins harbor ill-defined chaperone and prolyl isomerase activities toward physiological substrates. Results: Nonoverlapping chaperone or prolyl isomerase activity loss of Ran-binding protein 2 (Ranbp2) cyclophilin domain triggers unique impairments of proteostasis in distinct cell types and ubiquitin-proteasome system. Conclusion: Ranbp2 cyclophilin subdomains present discriminating physiological activities toward substrates or regulation of ubiquitin-proteasome system. Significance: Ranbp2-mediated mechanistic links in proteostasis with physiological and therapeutic relevance are uncovered.The immunophilins, cyclophilins, catalyze peptidyl cis-trans prolyl-isomerization (PPIase), a rate-limiting step in protein folding and a conformational switch in protein function. Cyclophilins are also chaperones. Noncatalytic mutations affecting the only cyclophilins with known but distinct physiological substrates, the Drosophila NinaA and its mammalian homolog, cyclophilin-B, impair opsin biogenesis and cause osteogenesis imperfecta, respectively. However, the physiological roles and substrates of most cyclophilins remain unknown. It is also unclear if PPIase and chaperone activities reflect distinct cyclophilin properties. To elucidate the physiological idiosyncrasy stemming from potential cyclophilin functions, we generated mice lacking endogenous Ran-binding protein-2 (Ranbp2) and expressing bacterial artificial chromosomes of Ranbp2 with impaired C-terminal chaperone and with (Tg-Ranbp2 WT-HA ) or without PPIase activities (Tg-Ranbp2 R2944A-HA ). The transgenic lines exhibit unique effects in proteostasis. Either line presents selective deficits in M-opsin biogenesis with its accumulation and aggregation in cone photoreceptors but without proteostatic impairment of two novel Ranbp2 cyclophilin partners, the cytokine-responsive effectors, STAT3/STAT5. Peptidyl cis-trans-prolyl isomerization is a rate-limiting step in protein folding (1-3). The catalysis of the cis-trans interconversion of the peptidyl-prolyl isomers is catalyzed by peptidylprolyl cis-trans isomerases (PPIase) 5 (4 -6). PPIases compose three families of structurally unrelated proteins, the cyclophilins (CyP), FK506-binding proteins (FKBP), and parvulins (7). * This work was supported, in whole or in part, by National Institutes of Health Grants EY019492, GM083165, and GM083165-03S1 (to P. A. F.), 2P30-EY005722 (to Duke University Eye Center), and 5P30NS061789 (to Duke Neurotransgenic Laboratory). This work was also supported by the Foundation Fighting CyPs and FKBPs are designated also as immunophilins, because they mediate immunosuppression (8,9). This effect is achieved by a gain-of-function mechanism upon binding of the immunosuppressive metabolites, cyclosporin A (CsA) or FK506, to the PPIase active site and formation of a ternary complex with the serine/threonine phosphatase, calcineurin, whose sequestration and inhibition prevents the dephosphorylation and activation of the nuclear factor for activation of T-cells (9 -12). Howe...
Intracerebral hemorrhage (ICH) is a devastating form of stroke. In this study, we examined the efficacy of deferoxamine (DFX), an iron chelator, after collagenase-induced ICH in 12-month-old mice. Intracerebral hemorrhage was induced by intrastriatal injection of collagenase. Deferoxamine (200 mg/kg, intraperitoneal) or vehicle was administrated 6 hours after ICH and then every 12 hours for up to 3 days. Neurologic deficits were examined on days 1 and 3 after ICH. Mice were killed after 1 or 3 days of DFX treatment for examination of iron deposition, neuronal death, oxidative stress, microglia/astrocyte activation, neutrophil infiltration, brain injury volume, and brain edema and swelling. Collagenase-induced ICH resulted in iron overload in the perihematomal region on day 3. Systemic administration of DFX decreased iron accumulation and neuronal death, attenuated production of reactive oxygen species, and reduced microglial activation and neutrophil infiltration without affecting astrocytes. Although DFX did not reduce brain injury volume, edema, or swelling, it improved neurologic function. Results of our study indicate that iron toxicity contributes to collagenase-induced hemorrhagic brain injury and that reducing iron accumulation can reduce neuronal death and modestly improve functional outcome after ICH in mice.
We have developed an association-based approach using classical inbred strains of mice in which we correct for population structure, which is very extensive in mice, using an efficient mixed-model algorithm. Our approach includes inbred parental strains as well as recombinant inbred strains in order to capture loci with effect sizes typical of complex traits in mice (in the range of 5 % of total trait variance). Over the last few years, we have typed the hybrid mouse diversity panel (HMDP) strains for a variety of clinical traits as well as intermediate phenotypes and have shown that the HMDP has sufficient power to map genes for highly complex traits with resolution that is in most cases less than a megabase. In this essay, we review our experience with the HMDP, describe various ongoing projects, and discuss how the HMDP may fit into the larger picture of common diseases and different approaches.
The clinical success of stem cell therapy for myocardial repair hinges on a better understanding of cardiac fate mechanisms. We have identified small molecules involved in cardiac fate by screening a chemical library for activators of the signature gene Nkx2.5, using a luciferase knockin bacterial artificial chromosome (BAC) in mouse P19CL6 pluripotent stem cells. We describe a family of sulfonylhydrazone (Shz) small molecules that can trigger cardiac mRNA and protein expression in a variety of embryonic and adult stem/progenitor cells, including human mobilized peripheral blood mononuclear cells (M-PBMCs). Small-molecule-enhanced M-PBMCs engrafted into the rat heart in proximity to an experimental injury improved cardiac function better than control cells. Recovery of cardiac function correlated with persistence of viable human cells, expressing humanspecific cardiac mRNAs and proteins. Shz small molecules are promising starting points for drugs to promote myocardial repair/ regeneration by activating cardiac differentiation in M-PBMCs.cardiogenesis ͉ chemical biology ͉ high-throughput screen ͉ myocardial repair
Background Chronic stress-induced cardiac pathology exhibits both a wide range in severity and a high degree of heterogeneity in clinical manifestation in human patients. This variability is contributed to by complex genetic and environmental etiologies within the human population. Genetic approaches to elucidate the genetics underlying the acquired forms of cardiomyopathies, including genome-wide association studies (GWAS), have been largely unsuccessful, resulting in limited knowledge as to the contribution of genetic variations for this important disease. Methods and Results Using the β-adrenergic agonist isoproterenol as a specific pathological stressor to circumvent the problem of etiological heterogeneity, we performed a GWAS for genes influencing cardiac hypertrophy and fibrosis in a large panel of inbred mice. Our analyses revealed 7 significant loci and 17 suggestive loci, containing an average of 14 genes, affecting cardiac hypertrophy, fibrosis and surrogate traits relevant to HF. Several loci contained candidate genes which are known to contribute to Mendelian cardiomyopathies in humans or have established roles in cardiac pathology based on molecular or genetic studies in mouse models. In particular, we identify Abcc6 as the gene underlying a fibrosis locus by validating that an allele with a splice mutation of Abcc6 dramatically and rapidly promotes isoproterenol induced cardiac fibrosis. Conclusions Genetic variants significantly contribute to the phenotypic heterogeneity of stress induced cardiomyopathy. Systems genetics is an effective approach to identify genes and pathways underlying the specific pathological features of cardiomyopathies. Abcc6 is a previously unrecognized player in the development of stress-induced cardiac fibrosis.
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