Abstract 201: Enhancing Pgc-1α Activity Improves Heart Function Through Activating Mitochondrial Biogenesis in Chagas Disease

2015 ◽  
Vol 117 (suppl_1) ◽  
Author(s):  
Xianxiu Wan ◽  
Jianjun Wen ◽  
Koo Sue-jie

Chronic chagasic cardiomyopathy (CCM) is presented with ventricular hypertrophy and contractile dysfunction that can lead to heart failure. I have found that a substantial decline in mitochondrial biogenesis and SIRT1/PGC-1α activity ensue in chronic chagasic mice. It was evidenced by the decline in mitochondrial DNA content as well as mRNA levels of mitochondrial encoded genes and mtDNA replication machinery. Further, the activity of SIRT1 (required for PGC-1α activation) was decreased and associated with decreased nuclear levels of PGC-1-regulated NRF1 transcription factor in chagasic hearts. The mitochondrial size and number were also reduced in chagasic heart, determined by electron microscopy. Therefore, we hypothesized that enhancing the SIRT1/PGC-1α activity by SIRT1 agonist would improve heart function through activating mitochondrial biogenesis in Chagasic disease. Mice were infected with T. cruzi, and beginning at day 90 post-infection (pi), treated with resveratrol (SIRT1 agonist) or metformin (AMPK agonist, can enhance SIRT1 activity) for 21 days; and then heart function was monitored at 150 days pi. We found that treatment with resveratrol partially attenuated the heart dysfunction (stroke volume, cardiac output, ejection fraction, heart rate) and cardiac hypertrophy in chagasic mice. These benefits were associated with improved expression of the mitochondrial DNA encoded genes and mtDNA content though the expression of genes involved in mtDNA replication was not improved. Treatment with metformin was not significantly beneficial in improving the CCM outcomes. The partial beneficial effects of resveratrol could be due to inefficient activation of SIRT1 or delayed start of the treatment. We plan to treat mice with SIRT1 agonist SIRT1720 (10 fold more active than resveratrol) during the indeterminate phase of T. cruzi infection in next set of experiments. This study will improve our understanding of the molecular and immune mechanisms of chagasic heart disease and will provide a novel treatment for chronically-infected chagasic patients.

2020 ◽  
Vol 21 (4) ◽  
pp. 1196 ◽  
Author(s):  
Serazhutdin Abdullaev ◽  
Nina Gubina ◽  
Tatiana Bulanova ◽  
Azhub Gaziev

Studies of molecular changes occurred in various brain regions after whole-body irradiation showed a significant increase in terms of the importance in gaining insight into how to slow down or prevent the development of long-term side effects such as carcinogenesis, cognitive impairment and other pathologies. We have analyzed nDNA damage and repair, changes in mitochondrial DNA (mtDNA) copy number and in the level of mtDNA heteroplasmy, and also examined changes in the expression of genes involved in the regulation of mitochondrial biogenesis and dynamics in three areas of the rat brain (hippocampus, cortex and cerebellum) after whole-body X-ray irradiation. Long amplicon quantitative polymerase chain reaction (LA-QPCR) was used to detect nDNA and mtDNA damage. The level of mtDNA heteroplasmy was estimated using Surveyor nuclease technology. The mtDNA copy numbers and expression levels of a number of genes were determined by real-time PCR. The results showed that the repair of nDNA damage in the rat brain regions occurs slowly within 24 h; in the hippocampus, this process runs much slower. The number of mtDNA copies in three regions of the rat brain increases with a simultaneous increase in mtDNA heteroplasmy. However, in the hippocampus, the copy number of mutant mtDNAs increases significantly by the time point of 24 h after radiation exposure. Our analysis shows that in the brain regions of irradiated rats, there is a decrease in the expression of genes (ND2, CytB, ATP5O) involved in ATP synthesis, although by the same time point after irradiation, an increase in transcripts of genes regulating mitochondrial biogenesis is observed. On the other hand, analysis of genes that control the dynamics of mitochondria (Mfn1, Fis1) revealed that sharp decrease in gene expression level occurred, only in the hippocampus. Consequently, the structural and functional characteristics of the hippocampus of rats exposed to whole-body radiation can be different, most significantly from those of the other brain regions.


2020 ◽  
Author(s):  
Petey Mumford ◽  
Shelby Osburn ◽  
Michael D. Roberts

Abstract There is evidence in rodents to suggest theacrine-based supplements modulate tissue sirtuin activity as well as other biological processes associated with aging. Herein, we examined if a theacrine-based supplement (NAD3) altered sirtuin activity in vitro while also affecting markers of mitochondrial biogenesis and the mRNA expression of genes related to various cellular processes in muscle. The murine C2C12 myoblast cell line was used for experimentation. Following 7 days of differentiation, myotubes were treated with 0.45 mg/mL of NAD3 (containing ~ 2 mM theacrine) for 3 and 24 hours (n=6 treatment wells per time point). Control treatments consisted of cellulose-only treatments at the same time points. Relative to CTL-treated cells, NAD3 treatments increased (p<0.05) Sirt1 mRNA levels at 3 hours, as well as global sirtuin activity at 3 and 24 hours. While NAD3 treatments decreased mRNA levels of Nfe2l2 at 3 hours and increased levels at 24 hours relative to CTL-treated cells (a gene involved in mitochondrial biogenesis, p<0.05), citrate synthase activity levels (a surrogate of mitochondrial density) remained unaltered between treatments. NAD3 treatments for 3 and 24 hours decreased Nlrp3 mRNA levels relative to CTL-treated cells (an inflammatory marker, p<0.05). Additionally, NAD3 treatments decreased Map1lc3b mRNA levels (an autophagy marker) after 24-hour treatments (p<0.05). Although these data are limited to select biomarkers in vitro, these preliminary findings suggest a theacrine-based supplement can modulate various skeletal muscle biomarkers related to sirtuin activity, inflammation, and autophagy. Muscle biopsy studies in humans are needed to confirm these current findings.


Molecules ◽  
2018 ◽  
Vol 23 (8) ◽  
pp. 1853 ◽  
Author(s):  
Mak-Soon Lee ◽  
Yangha Kim

Isorhamnetin (ISOR), 3-O-methylquercetin, is a naturally occurring flavonoid in many plants. It is a metabolite derived from quercetin and is known to exert beneficial effects on the prevention of obesity. However, the molecular mechanism of action involved in ISOR-mediated mitochondrial biogenesis, and AMP-activated protein kinase (AMPK) activation in 3T3-L1 cells remains unclear. The aim of this study was to determine whether ISOR affected mitochondrial biogenesis and AMPK activation, during 3T3-L1 adipocyte differentiation. Intracellular lipid and triglyceride accumulation, and glycerol-3-phosphate dehydrogenase (GPDH) activity decreased in ISOR-treated cells. The mRNA levels of adipogenic genes, such as the proliferator-activated receptor-γ (PPAR-γ), and adipocyte protein 2 (aP2), were inhibited by ISOR. In contrast, mRNA levels of mitochondrial genes, such as peroxisome proliferator-activated reporter gamma coactivator-1α (PGC-1α), nuclear respiratory factor (NRF)-1, transcription factor A (Tfam), and carnitine palmitoyl transferase-1α (CPT-1α), were all stimulated by ISOR treatment. Mitochondria DNA (mtDNA) copy number and AMPK activity were also stimulated by ISOR. The results suggested that the mitochondrial biogenic effect of ISOR in adipocytes might have been associated with stimulation of mitochondrial gene expression, mtDNA replication, and AMPK activation.


Author(s):  
Su Bu ◽  
Chunying Yuan ◽  
Fuliang Cao ◽  
Qifeng Xu ◽  
Yichun Zhang ◽  
...  

Background: The fruit Prunus mume has beneficial effects in the treatment of obesity and metabolic syndrome. However, its mechanism of action is unclear. Objective: We assessed the effect of a concentrated water extract of P. mume fruit (CEPM) on adipogenesis and beiging/browning in 3T3-L1 cells. Methods: The cell viability was determined by MTT assay. Lipid accumulation was assessed with Oil Red O (ORO) staining under different concentrations of CEPM. The effects of CEPM treatment during differentiation on beiging/browning and mitochondrial biogenesis in 3T3-L1 cells were investigated. Results: CEPM treatment suppressed differentiation and decreased lipid accumulation by downregulating the expression of key adipogenic genes, including PPARγ, C/EBPα, SREBP-1c, FAS, and perilipin A. In contrast, CEPM treatment increased the mitochondrial DNA (mtDNA) content and mRNA levels of mitochondrial biogenesis genes, including NAMPT, Nrf1, Nrf2, and CPT1α, and reduced reactive oxygen species levels. Importantly, CEPM increased the expression of brown/beige hallmark genes (Pgc-1α, Ucp1, Cidea, Cox7α1, Cox8b, Cd137, and Pdk-4), as well as proteins (UCP1, PGC-1α, NRF1, TBX1, and CPT1α). The high-performance liquid chromatography (HPLC) analysis reveals that CEPM contains mumefural, naringin, 5-HMF, citric acid, caffeic acid, and hesperidin. Conclusion: The first evidence we provided showed that CEPM has a dual role in 3T3-L1 cells inhibiting adipogenesis and promoting beiging/browning, and hence, could be a potential agent in the fight against obesity.


Antioxidants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1002
Author(s):  
Fabiola Marino ◽  
Mariangela Scalise ◽  
Eleonora Cianflone ◽  
Luca Salerno ◽  
Donato Cappetta ◽  
...  

Over the years strong evidence has been accumulated showing that aerobic physical exercise exerts beneficial effects on the prevention and reduction of cardiovascular risk. Exercise in healthy subjects fosters physiological remodeling of the adult heart. Concurrently, physical training can significantly slow-down or even reverse the maladaptive pathologic cardiac remodeling in cardiac diseases, improving heart function. The underlying cellular and molecular mechanisms of the beneficial effects of physical exercise on the heart are still a subject of intensive study. Aerobic activity increases cardiovascular nitric oxide (NO) released mainly through nitric oxidase synthase 3 activity, promoting endothelium-dependent vasodilation, reducing vascular resistance, and lowering blood pressure. On the reverse, an imbalance between increasing free radical production and decreased NO generation characterizes pathologic remodeling, which has been termed the “nitroso-redox imbalance”. Besides these classical evidence on the role of NO in cardiac physiology and pathology, accumulating data show that NO regulate different aspects of stem cell biology, including survival, proliferation, migration, differentiation, and secretion of pro-regenerative factors. Concurrently, it has been shown that physical exercise generates physiological remodeling while antagonizes pathologic remodeling also by fostering cardiac regeneration, including new cardiomyocyte formation. This review is therefore focused on the possible link between physical exercise, NO, and stem cell biology in the cardiac regenerative/reparative response to physiological or pathological load. Cellular and molecular mechanisms that generate an exercise-induced cardioprotective phenotype are discussed in regards with myocardial repair and regeneration. Aerobic training can benefit cells implicated in cardiovascular homeostasis and response to damage by NO-mediated pathways that protect stem cells in the hostile environment, enhance their activation and differentiation and, in turn, translate to more efficient myocardial tissue regeneration. Moreover, stem cell preconditioning by and/or local potentiation of NO signaling can be envisioned as promising approaches to improve the post-transplantation stem cell survival and the efficacy of cardiac stem cell therapy.


Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1282
Author(s):  
Ariuntsetseg Khurelchuluun ◽  
Osamu Uehara ◽  
Durga Paudel ◽  
Tetsuro Morikawa ◽  
Yutaka Kawano ◽  
...  

Background: Bee pollen (BP) has a broad range of beneficial effects on health. The aim of this study was to examine the effect of BP on the oral environment, including the microbiome and antimicrobial peptides. Methods: C57BL/6J mice were randomly divided into two groups: control and BP. The BP group was fed with a 5% BP diet for 1 month. Swabs from the oral and buccal mucosa and samples of the intestinal stool were collected. Genomic DNA was extracted and the microbiome was analyzed via 16S rRNA sequencing. Results: BP inhibited the growth of P. gingivalis at a concentration of >2.5%. The metagenomic study showed that the abundance of genus Lactococcus was significantly elevated in the oral and intestinal microbiomes of the BP group when compared to those of the control group. Significant alterations in alpha and beta diversity were observed between the oral microbiomes of the two groups. The mRNA levels of beta-defensin-2 and -3 were significantly upregulated in the buccal mucosa of the BP group. Conclusion: A BP diet may have a beneficial effect on oral and systemic health by modulating the bacterial flora and antimicrobial peptides of the oral cavity. Further investigations are needed to clarify how a BP diet affects overall human health.


Biomolecules ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 393
Author(s):  
Oliver Neuhaus ◽  
Wolfgang Köhler ◽  
Florian Then Bergh ◽  
Wolfgang Kristoferitsch ◽  
Jürgen Faiss ◽  
...  

Although fatigue is a common symptom in multiple sclerosis (MS), its pathomechanisms are incompletely understood. Glatiramer acetate (GA), an immunomodulatory agent approved for treatment of relapsing-remitting MS (RRMS), possesses unique mechanisms of action and has been shown to exhibit beneficial effects on MS fatigue. The objective of this study was to correlate clinical, neuropsychological, and immunological parameters in RRMS patients with fatigue before and during treatment with GA. In a prospective, open-label, multicenter trial, 30 patients with RRMS and fatigue were treated with GA for 12 months. Inclusion criterion was the presence of fatigue as one of the most frequent and disabling symptoms. Before and during treatment, fatigue was assessed using the Fatigue Severity Scale (FSS), the MS-FSS, and the Modified Fatigue Impact Scale (MFIS). In addition, fatigue and quality of life were assessed using the Visual Analog Scales (VAS). Laboratory assessments included screening of 188 parameters using real-time PCR microarrays followed by further analysis of several cytokines, chemokines, and neurotrophic factors. Fatigue self-assessments were completed in 25 patients. After 12 months of treatment with GA, 13 of these patients improved in all three scales (with the most prominent effects on the MFIS), whereas 5 patients had deteriorated. The remaining 7 patients exhibited inconsistent effects within the three scales. Fatigue and overall quality of life had improved, as assessed via VAS. Laboratory assessments revealed heterogeneous mRNA levels of cytokines, chemokines, and neurotrophic factors. In conclusion, we were not able to correlate clinical and molecular effects of GA in patients with RRMS and fatigue.


2012 ◽  
Vol 7 (2) ◽  
pp. 192-200
Author(s):  
Jacek Turyn ◽  
Adriana Mika ◽  
Piotr Stepnowski ◽  
Julian Swierczynski

AbstractIt is generally accepted that the location of body fat deposits may play an important role in the risk of developing some endocrine and metabolic diseases. We have studied the effect of food restriction and food restriction/refeeding, often practiced by individuals trying to lose body weight, on the expression of genes which are associated with obesity and certain metabolic disorders in inguinal, epididymal, and perirenal rat white adipose tissues. Gene expression was analyzed by real time semi-quantitative polymerase chain reaction and by Western blot. We found that prolonged food restriction caused a significant decrease of body and adipose tissue mass as well as the increase of Scd1 and Elovl6 gene expressions in all main rat adipose tissue deposits. Food restriction/refeeding caused increases of: a) Scd1 and Elovl6 mRNA levels in adipose tissue, b) Scd1 protein level and c) desaturation index in adipose tissue. The increased expression of both genes was unusually high in inguinal adipose tissue. The results suggest that the increase of Scd1 and Elovl6 gene expressions in white adipose tissue by prolonged food restriction and prolonged food restriction/refeeding may contribute to accelerated fat recovery that often occurs in individuals after food restriction/refeeding.


2001 ◽  
Vol 90 (1) ◽  
pp. 389-396 ◽  
Author(s):  
Joe W. Gordon ◽  
Arne A. Rungi ◽  
Hidetoshi Inagaki ◽  
David A. Hood

Mitochondrial transcription factor A (Tfam) is a nuclear-encoded gene product that is imported into mitochondria and is required for the transcription of mitochondrial DNA (mtDNA). We hypothesized that conditions known to produce mitochondrial biogenesis in skeletal muscle would be preceded by an increase in Tfam expression. Therefore, rat muscle was stimulated (10 Hz, 3 h/day). Tfam mRNA levels were significantly elevated (by 55%) at 4 days and returned to control levels at 14 days. Tfam import into intermyofibrillar (IMF) mitochondria was increased by 52 and 61% ( P < 0.05) at 5 and 7 days, respectively. This corresponded to an increase in the level of import machinery components. Immunoblotting data indicated that IMF Tfam protein content was increased by 63% ( P < 0.05) at 7 days of stimulation. This was associated with a 49% ( P < 0.05) increase in complex formation at the mtDNA promoter and a 65% ( P< 0.05) increase in the levels of a mitochondrial transcript, cytochrome- c oxidase (COX) subunit III. Similarly, COX enzyme activity was elevated by 71% ( P < 0.05) after 7 days of contractile activity. These results indicate that early events in mitochondrial biogenesis include increases in Tfam mRNA, followed by accelerations in mitochondrial import and increased Tfam content, which correspond with increased binding to the mtDNA promoter region. This was accompanied by increased mitochondrial transcript levels and elevated COX activity. These data support the role of Tfam as a regulatory protein involved in contractile activity-induced mitochondrial biogenesis.


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