a key pathogen in periodontitis, is associated with neuroinflammation. Periodontal disease increases with age; 70.1% of adults 65 years and older have periodontal problems. However, the
- ...lipopolysaccharide (LPS)induced mitochondrial dysfunction in neurodegenerative diseases remains elusive. In this study, we investigated the possible role of
-LPS in mitochondrial dysfunction during neurodegeneration. We found that
-LPS treatment activated toll-like receptor (TLR) 4 signaling and upregulated the expression of Alzheimer's disease-related dementia and neuroinflammatory markers. Furthermore, the LPS treatment significantly exacerbated the production of reactive oxygen species and reduced the mitochondrial membrane potential. Our study highlighted the pivotal role of
-LPS in the repression of serum response factor (SRF) and its co-factor p49/STRAP that regulate the actin cytoskeleton. The LPS treatment repressed the genes involved in mitochondrial function and biogenesis.
-LPS negatively altered oxidative phosphorylation and glycolysis and reduced total adenosine triphosphate (ATP) production. Additionally, it specifically altered the mitochondrial functions in complexes I, II, and IV of the mitochondrial electron transport chain. Thus, it is conceivable that
-LPS causes mitochondrial dysfunction through oxidative stress and inflammatory events in neurodegenerative diseases.
CCG-1423 is a Rho A pathway inhibitor that has been reported to inhibit Rho/SRF-mediated transcriptional regulation. Serum response factor and its cofactors, which include ternary complex factors and ...myocardin-related transcription factors, regulate various cellular functions. In this study, we observed that CCG-1423 modulates the mitochondrial functions. The effect of this small molecule drug was determined by measuring mitochondrial function using an XFe96 Analyzer and an Oxygraph 2k (O2k) high-resolution respirometer. CCG-1423 treatment significantly reduced oxidative phosphorylation in a dose-dependent manner. However, CCG-1423 increased the glycolytic rate. We also observed that histone 4 at lysine-16 underwent hyperacetylation with the treatment of this drug. Immunolabeling with F-actin and MitoTracker revealed the alteration in the actin cytoskeleton and mitochondria. Taken together, our findings highlight a critical role of CCG-1423 in inhibiting the transcription of SRF/p49 and PGC-1α, β, resulting in the downregulation of mitochondrial genes, leading to the repression of mitochondrial oxidative phosphorylation and overall ATP reduction. This study provides a better understanding of the effects of CCG-1423 on mitochondria, which may be useful for the assessment of the potential clinical application of CCG-1423 and its derivatives.
In a recent randomized, double-blind, placebo-controlled trial, we were able to demonstrate the superiority of a dietary supplement composed of essential amino acids (EAAs) over whey protein, in ...older adults with low physical function. In this paper, we describe the comparative plasma protein expression in the same subject groups of EAAs vs whey. The plasma proteomics data was generated using SOMA scan assay. A total of twenty proteins were found to be differentially expressed in both groups with a 1.5-fold change. Notably, five proteins showed a significantly higher fold change expression in the EAA group which included adenylate kinase isoenzyme 1, casein kinase II 2-alpha, Nascent polypeptide-associated complex subunit alpha, peroxiredoxin-1, and peroxiredoxin-6. These five proteins might have played a significant role in providing energy for the improved cardiac and muscle strength of older adults with LPF. On the other hand, fifteen proteins showed slightly lower fold change expression in the EAA group. Some of these 15 proteins regulate metabolism and were found to be associated with inflammation or other comorbidities. Gene Ontology (GO) enrichment analysis showed the association of these proteins with several biological processes. Furthermore, protein–protein interaction network analysis also showed distinct networks between upregulated and downregulated proteins. In conclusion, the important biological roles of the upregulated proteins plus better physical function of participants in the EAAs vs whey group demonstrated that EAAs have the potential to improve muscle strength and physical function in older adults. This study was registered with ClinicalTrials.gov: NCT03424265 “Nutritional interventions in heart failure.”
When generating monoclonal antibodies (mAb) against small molecules, the chemical composition and molecular orientation of the drug-like hapten on the antigen is a crucial determinant. This is ...especially important when attempting to discover therapeutic mAb against the drugs of abuse (+)-methamphetamine (+)-METH, (+)-amphetamine (+)-AMP, and the related compound (+)-3,4-methylenedioxymethamphetamine (+)-MDMA, the plus isomer in the racemic mixture known as MDMA or ecstasy. The goal of these studies was to design and synthesize (+)-METH-like haptens with structural attributes that could make them effective for generating monoclonal antibodies for treating medical problems associated with these stimulant drugs of abuse. Five prototype (+)-METH-like haptens, which mimic structural aspects of these drugs, were synthesized and used to generate mAb. After screening for anti-(+)-METH IgG antibodies in more than 25,000 potential mouse hybridoma cell lines, one prototype mAb from each of the five haptens was selected and studied in detail for molecular properties and preclinical efficacy. The amino acid sequences of the IgG-variable regions, structural models, affinity, and ligand specificity of each mAb were then used to help elucidate important therapeutic characteristics. Four of these antibodies exhibited high affinity and specificity to (+)-METH and (+)-MDMA; whereas one antibody (designated mAb4G9) exhibited high affinity and specificity to (+)-METH, (+)-MDMA, and (+)-AMP, without significant cross-reactivity against other METH-like ligands, over-the-counter medications, or endogenous neurotransmitters. Considered together, discovery of mAb4G9 and the other antibodies in this report represent an important step in understanding the process for custom design of drug class-specific therapeutic antibodies for the treatment of drug addiction.
In addition to addiction, the repeated use of (+)-methamphetamine (+)-METH, (+)-amphetamine (+)-AMP, or (±)-3,4-methylenedioxymethamphetamine ((±)-MDMA, commonly called ecstasy) can lead to ...life-threatening medical problems including cardiovascular injury, severe depression, and psychosis. Currently, there are no specific pharmacotherapies to treat these medical problems. In this study, we report the design and synthesis of two haptens, (S)-(+)-3-(9-carboxynonyloxy)methamphetamine (3a, (+)-METH MO10) and (S)-(+)-3-(5-carboxypentyloxy)methamphetamine (3b, (+)-METH MO6), and their use in generating high affinity (low K D value) monoclonal antibodies (mAbs) against (+)-METH, (+)-AMP, and/or (+)-MDMA. On the basis of results from the determination of mAb K D values and ligand specificity, the mAbs generated from hapten 3a showed the greatest promise for generating active and passive immunotherapies for treating overdose or addiction from (+)-METH-like stimulants.
Abstract only
Renal ischemia is encountered in multiple clinical settings and frequently results in acute kidney injury (AKI) due to insufficient energy production to sustain renal functions. ...Ischemia‐induced mitochondrial dysfunction and ATP depletion result in disruption of the primary functions of the kidney in many affected hospitalized patients who suffer AKI, but are left without an effective treatment. This study tested whether γ‐tocotrienol (GT3), a member of the vitamin E family, promotes mitochondrial function, reduces ATP deficits and tissue damage, improves renal functions, and diminishes AKI after renal ischemia/reperfusion injury in mice. Mice were treated with vehicle or GT3 (200 mg/kg) 15h before or immediately after bilateral kidney ischemia, and end points were assessed in kidneys harvested at 24h, 72h, and 168h of reperfusion. GT3 treatment prior to and after ischemia reduced decreases in mitochondrial state 3 respiration and accelerated recovery of this function after ischemia. GT3 prevented the decreases in activities of NADH:Ubiquinone Oxidoreductase (complex I) and Ubiquinol:Cytochrome c Oxidoreductase (complex III) of the mitochondrial electron transport chain regardless of whether it was administered before or after ischemia. GT3 treatment also blocked ischemia‐induced decreases in ATP synthase (F
O
F
1
‐ATPase) activity and ATP content in renal cortical tissue. Furthermore, GT3 reduced renal tissue injury (decreased renal tubular necrosis and cast formation) and accelerated morphological regeneration of renal proximal tubules after ischemia. Kidneys of mice treated with GT3 displayed morphological improvements at 72h after ischemia by exhibiting fewer necrotic proximal tubules and inflammatory cells, while demonstrating increased tubular regeneration. GT3 treatment ameliorated increases in plasma creatinine levels and accelerated recovery of renal function after ischemia. Lastly, 89% of mice receiving GT3 and 70% of those receiving vehicle survived 72h after ischemia. In conclusions, GT3 administration improves mitochondrial respiratory functions and activity of F
O
F
1
‐ATPase, and prevents ATP deficits in ischemic kidneys. This is associated with improved kidney morphology, ameliorated decreases in renal functions, and increased survival after AKI.
Support or Funding Information
This research was supported by Arkansas Science & Technology Authority; Grant 15‐B‐27.
Abstract These studies examined the in vivo pharmacokinetics and efficacy of five anti-methamphetamine monoclonal antibodies (mAbs, KD values from 11 to 250 nM) in rats. While no substantive ...differences in mAb systemic clearance ( t1/2 = 6.1–6.9 days) were found, in vivo function was significantly reduced within 1–3 days for four of the five mAbs. Only mAb4G9 was capable of prolonged efficacy, as judged by prolonged high methamphetamine serum concentrations. MAb4G9 also maintained high amphetamine serum concentrations, along with reductions in methamphetamine and amphetamine brain concentrations, indicating neuroprotection. The combination of broad specificity for methamphetamine-like drugs, high affinity, and prolonged action in vivo suggests mAb4G9 is a potentially efficacious medication for treating human methamphetamine-related medical diseases.
Dietary proteins and essential amino acids (EAAs) are the major nutritional supplements that support the growth and activity of gut microbes contributing to the wellbeing of their host. This study ...hypothesizes that daily supplementation of the diet with either EAAs or whey protein for 12 weeks would improve the gut microbiome of older adults.
The stool samples are processed and subjected to Illumina-based 16S ribosomal ribonucleic acid (rRNA) gene amplicon sequencing. In both groups, the most abundant families are found in order of relative abundance included: Bacteroidaceae, Lachnospiraceae, Ruminococcaceae, Prevotellaceae, Rikenellaceae, Enterobacteriaceae, Oscillospiraceae, Tannerellaceae, and Akkermansiaceae, which indicate that these subjects are able to maintain a same healthy microbial diversity in their guts. A significant finding is a reduction of proinflammatory cytokine, interleukin-18 (IL-18) in the EAAs group. It also uses the standard 6-min walking test (6MWT) as a measure of cardiopulmonary fitness. At the end of the study, the subjects in the EAAs group perform significantly better in the 6MWT as compared to the whey group.
It seems plausible that the improved physical performance and reduced proinflammatory cytokine, IL-18 seen in the EAAs group, are independent of changes in gut microbiota.
Abstract
Background
Alternative splicing (AS) is a mechanism that generates multiple mRNA transcripts and protein isoforms from a single gene, thereby increasing transcriptomic and proteomic ...diversity. The spliced isoforms commonly lack one or more exons, which may have similar or even opposite functions. Alternatively spliced isoforms tend to increase during aging. The sirtuin-1 gene contains multiple exons and undergoes alternative splicing, which generates multiple isoforms. In this study, we assessed the impact of three sirtuin-1 isoforms on mitochondrial gene expression and function in muscle cells.
Methods
Three sirtuin-1 isoforms (V1, V2, V3) were subcloned into expression vectors. Muscle cell lines (H9C2 and C2C12) were transfected with sirtuin-1 isoforms, respectively. Microscopic images were obtained using a Nikon microscope. Gene expression was determined by quantitative RT-PCR and Western blotting. The mitochondrial function was determined with a Seahorse XFe96 Analyzer. Results and conclusions The sirtuin-1 V1 isoform significantly increased the oxygen consumption rate (OCR) and decreased glycolysis (ECAR) in muscle cells, while V2 and V3 isoforms had slight or no significant effect on OCR and ECAR. V1 isoform was localized in the nucleus, whereas V2 and V3 were localized in the cytoplasm. Sirtuin-1 isoforms differentially impacted mitochondrial complex genes, including NDUFS1, NDUFV1, NDUFV2, NDUFA5. Our data indicate that the domain loss changed sirtuin-1 isoform subcellular localization, differentially impacted mitochondrial gene expression, and affected mitochondrial function. The age-related change in the expression of sirtuin-1 isoforms could affect cardiac and skeletal muscle function in aging and senescence. Further exploration of the sirtuin-1 isoforms’ functions is warranted.
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