The Combination Effect of Aspalathin and Phenylpyruvic Acid-2-O-β-d-glucoside from Rooibos against Hyperglycemia-Induced Cardiac Damage: An In Vitro Study

Recent evidence shows that rooibos compounds, aspalathin and phenylpyruvic acid-2-O-β-d-glucoside (PPAG), can independently protect cardiomyocytes from hyperglycemia-related reactive oxygen species (ROS). While aspalathin shows more potency by enhancing intracellular antioxidant defenses, PPAG acts more as an anti-apoptotic agent. Thus, to further understand the protective capabilities of these compounds against hyperglycemia-induced cardiac damage, their combinatory effect was investigated and compared to metformin. An in vitro model of H9c2 cardiomyocytes exposed to chronic glucose concentrations was employed to study the impact of such compounds on hyperglycemia-induced damage. Here, high glucose exposure impaired myocardial substrate utilization by abnormally enhancing free fatty acid oxidation while concomitantly suppressing glucose oxidation. This was paralleled by altered expression of genes involved in energy metabolism including acetyl-CoA carboxylase (ACC), 5′ AMP-activated protein kinase (AMPK), and peroxisome proliferator-activated receptor-alpha (PPARα). The combination treatment improved myocardial substrate metabolism, maintained mitochondrial membrane potential, and attenuated various markers for oxidative stress including nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity and glutathione content. It also showed a much-improved effect by ameliorating DNA damage when compared to metformin. The current study demonstrates that rooibos compounds offer unique cardioprotective properties against hyperglycemia-induced and potentially against diabetes-induced cardiac damage. These data also support further exploration of rooibos compounds to better assess the cardioprotective effects of different bioactive compound combinations.

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Adipocyte PHLPP2 inhibition prevents obesity-induced fatty liver

Nature Communications ◽

10.1038/s41467-021-22106-2 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

KyeongJin Kim ◽

Jin Ku Kang ◽

Young Hoon Jung ◽

Sang Bae Lee ◽

Raffaela Rametta ◽

...

Keyword(s):

Fatty Liver ◽

Whole Body ◽

Acid Oxidation ◽

Chow Diet ◽

Peroxisome Proliferator ◽

Obese Mice ◽

Ph Domain ◽

Peroxisome Proliferator Activated Receptor

AbstractIncreased adiposity confers risk for systemic insulin resistance and type 2 diabetes (T2D), but mechanisms underlying this pathogenic inter-organ crosstalk are incompletely understood. We find PHLPP2 (PH domain and leucine rich repeat protein phosphatase 2), recently identified as the Akt Ser473 phosphatase, to be increased in adipocytes from obese mice. To identify the functional consequence of increased adipocyte PHLPP2 in obese mice, we generated adipocyte-specific PHLPP2 knockout (A-PHLPP2) mice. A-PHLPP2 mice show normal adiposity and glucose metabolism when fed a normal chow diet, but reduced adiposity and improved whole-body glucose tolerance as compared to Cre- controls with high-fat diet (HFD) feeding. Notably, HFD-fed A-PHLPP2 mice show increased HSL phosphorylation, leading to increased lipolysis in vitro and in vivo. Mobilized adipocyte fatty acids are oxidized, leading to increased peroxisome proliferator-activated receptor alpha (PPARα)-dependent adiponectin secretion, which in turn increases hepatic fatty acid oxidation to ameliorate obesity-induced fatty liver. Consistently, adipose PHLPP2 expression is negatively correlated with serum adiponectin levels in obese humans. Overall, these data implicate an adipocyte PHLPP2-HSL-PPARα signaling axis to regulate systemic glucose and lipid homeostasis, and suggest that excess adipocyte PHLPP2 explains decreased adiponectin secretion and downstream metabolic consequence in obesity.

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Abstract 83: Modulation of Macrophage Function via Metabolism by Trypanosoma cruzi

Circulation Research ◽

10.1161/res.117.suppl_1.83 ◽

2015 ◽

Vol 117 (suppl_1) ◽

Author(s):

Sue-Jie Koo ◽

Nisha J Garg

Keyword(s):

Trypanosoma Cruzi ◽

Chronic Phase ◽

Etiologic Agent ◽

Acid Oxidation ◽

Peroxisome Proliferator ◽

Transcription Control ◽

Metabolic Gene Expression ◽

Anti Inflammatory ◽

Peroxisome Proliferator Activated Receptors ◽

The Impact

Chagas heart disease is an inflammatory cardiomyopathy which presents with mononuclear infiltrates in the interstitium and myocardial fibrosis in the chronic phase. Incomplete clearance by macrophages of the etiologic agent, Trypanosoma cruzi , is a significant cause of chronic disease development in approximately 30% of those serologically positive for the blood-borne parasite. The differential metabolic status, anaerobic glycolysis and mitochondria-dependent oxidative phosphorylation, are respectively associated with pro-inflammatory (M1) and anti-inflammatory (M2) functional activation of macrophages. Reactive oxygen species (ROS) have been shown to be an intracellular signal for glycolysis while peroxisome proliferator-activated receptors (PPARs) that enhance fatty acid oxidation provide transcription control of macrophage functional state. In our studies using diverse T. cruzi isolates, we showed that SylvioX10 (virulent), but not TCC (non-virulent), isolates are able to differentially control extracellular and intracellular ROS levels in macrophages. We found in macrophages infected with SylvioX10, the nuclear expression of PPAR-α was increased by 18 hours post-infection, and mitochondrial metabolic activity was similar to that of not-infected and M2 controls; which indicates anti-inflammatory function of macrophages, and therefore prohibiting T. cruzi clearance. In our ongoing studies, we are examining the impact of PPAR-α inhibitors in modulating the metabolic gene expression profile, functional phenotype and parasite survival in macrophages. Our data will provide the first indication that host macrophages have deficient pro-inflammatory capacity due to sub-optimal glucose oxidation, and enhancing the metabolism that supports T. cruzi clearance will provide a valuable basis for a strategy to arrest Chagas disease progression.

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Role of Hyaluronan in Human Adipogenesis: Evidence from in-Vitro and in-Vivo Studies

International Journal of Molecular Sciences ◽

10.3390/ijms20112675 ◽

2019 ◽

Vol 20 (11) ◽

pp. 2675 ◽

Cited By ~ 1

Author(s):

Nicholas Wilson ◽

Robert Steadman ◽

Ilaria Muller ◽

Mohd Draman ◽

D. Aled Rees ◽

...

Keyword(s):

Stem Cell Differentiation ◽

In Vivo Studies ◽

Peroxisome Proliferator ◽

Synthesis Inhibitor ◽

Peroxisome Proliferator Activated Receptor ◽

Inhibitory Role ◽

The Impact

Hyaluronan (HA), an extra-cellular matrix glycosaminoglycan, may play a role in mesenchymal stem cell differentiation to fat but results using murine models and cell lines are conflicting. Our previous data, illustrating decreased HA production during human adipogenesis, suggested an inhibitory role. We have investigated the role of HA in adipogenesis and fat accumulation using human primary subcutaneous preadipocyte/fibroblasts (PFs, n = 12) and subjects of varying body mass index (BMI). The impact of HA on peroxisome proliferator-activated receptor gamma (PPARγ) expression was analysed following siRNA knockdown or HA synthase (HAS)1 and HAS2 overexpression. PFs were cultured in complete or adipogenic medium (ADM) with/without 4-methylumbelliferone (4-MU = HA synthesis inhibitor). Adipogenesis was evaluated using oil red O (ORO), counting adipogenic foci, and measurement of a terminal differentiation marker. Modulating HA production by HAS2 knockdown or overexpression increased (16%, p < 0.04) or decreased (30%, p = 0.01) PPARγ transcripts respectively. The inhibition of HA by 4-MU significantly enhanced ADM-induced adipogenesis with 1.52 ± 0.18- (ORO), 4.09 ± 0.63- (foci) and 2.6 ± 0.21-(marker)-fold increases compared with the controls, also increased PPARγ protein expression (40%, (p < 0.04)). In human subjects, circulating HA correlated negatively with BMI and triglycerides (r = −0.396 (p = 0.002), r = −0.269 (p = 0.038), respectively), confirming an inhibitory role of HA in human adipogenesis. Thus, enhancing HA action may provide a therapeutic target in obesity.

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Effects of Dietary Anaplerotic and Ketogenic Energy Sources on Renal Fatty Acid Oxidation Induced by Clofibrate in Suckling Neonatal Pigs

International Journal of Molecular Sciences ◽

10.3390/ijms21030726 ◽

2020 ◽

Vol 21 (3) ◽

pp. 726

Author(s):

Xi Lin ◽

Brandon Pike ◽

Jinan Zhao ◽

Yu Fan ◽

Yongwen Zhu ◽

...

Keyword(s):

Fatty Acid ◽

Palmitic Acid ◽

Fatty Acid Oxidation ◽

Energy Sources ◽

Acid Oxidation ◽

Peroxisome Proliferator ◽

Fresh Tissue ◽

Peroxisome Proliferator Activated Receptor ◽

Tissue Homogenates

Maintaining an active fatty acid metabolism is important for renal growth, development, and health. We evaluated the effects of anaplerotic and ketogenic energy sources on fatty acid oxidation during stimulation with clofibrate, a pharmacologic peroxisome proliferator-activated receptor α (PPARα) agonist. Suckling newborn pigs (n = 72) were assigned into 8 dietary treatments following a 2 × 4 factorial design: ± clofibrate (0.35%) and diets containing 5% of either (1) glycerol-succinate (GlySuc), (2) tri-valerate (TriC5), (3) tri-hexanoate (TriC6), or (4) tri-2-methylpentanoate (Tri2MPA). Pigs were housed individually and fed the iso-caloric milk replacer diets for 5 d. Renal fatty acid oxidation was measured in vitro in fresh tissue homogenates using [1-14C]-labeled palmitic acid. The oxidation was 30% greater in pig received clofibrate and 25% greater (p < 0.05) in pigs fed the TriC6 diet compared to those fed diets with GlySuc, TriC5, and Tri2MPA. Addition of carnitine also stimulated the oxidation by twofold (p < 0.05). The effects of TriC6 and carnitine on palmitic acid oxidation were not altered by clofibrate stimulation. However, renal fatty acid composition was altered by clofibrate and Tri2MPA. In conclusion, modification of anaplerosis or ketogenesis via dietary substrates had no influence on in vitro renal palmitic acid oxidation induced by PPARα activation.

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Regulation of phagolysosomal activity by miR-204 critically influences structure and function of retinal pigment epithelium/retina

Human Molecular Genetics ◽

10.1093/hmg/ddz171 ◽

2019 ◽

Vol 28 (20) ◽

pp. 3355-3368 ◽

Cited By ~ 2

Author(s):

Congxiao Zhang ◽

Kiyoharu J Miyagishima ◽

Lijin Dong ◽

Aaron Rising ◽

Malika Nimmagadda ◽

...

Keyword(s):

Retinal Pigment Epithelium ◽

Pigment Epithelium ◽

Retinal Pigment ◽

Primary Cultures ◽

Structure And Function ◽

Apical Surface ◽

Altered Expression ◽

And Function ◽

The Impact

Abstract MicroRNA-204 (miR-204) is expressed in pulmonary, renal, mammary and eye tissue, and its reduction can result in multiple diseases including cancer. We first generated miR-204−/− mice to study the impact of miR-204 loss on retinal and retinal pigment epithelium (RPE) structure and function. The RPE is fundamentally important for maintaining the health and integrity of the retinal photoreceptors. miR-204−/− eyes evidenced areas of hyper-autofluorescence and defective photoreceptor digestion, along with increased microglia migration to the RPE. Migratory Iba1+ microglial cells were localized to the RPE apical surface where they participated in the phagocytosis of photoreceptor outer segments (POSs) and contributed to a persistent build-up of rhodopsin. These structural, molecular and cellular outcomes were accompanied by decreased light-evoked electrical responses from the retina and RPE. In parallel experiments, we suppressed miR-204 expression in primary cultures of human RPE using anti-miR-204. In vitro suppression of miR-204 in human RPE similarly showed abnormal POS clearance and altered expression of autophagy-related proteins and Rab22a, a regulator of endosome maturation. Together, these in vitro and in vivo experiments suggest that the normally high levels of miR-204 in RPE can mitigate disease onset by preventing generation of oxidative stress and inflammation originating from intracellular accumulation of undigested photoreactive POS lipids. More generally, these results implicate RPE miR-204-mediated regulation of autophagy and endolysosomal interaction as a critical determinant of normal RPE/retina structure and function.

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S100A4 promotes colorectal carcinoma growth by enhancing aerobic glycolysis

10.21203/rs.2.22923/v2 ◽

2020 ◽

Author(s):

Guiyang Wu ◽

Chongshan Wu ◽

Fubo Ye ◽

Xiongwen Zhu ◽

Zaiping Chen

Keyword(s):

Cancer Cell ◽

Proportional Hazards Model ◽

Aerobic Glycolysis ◽

Critical Role ◽

Cox Proportional Hazards ◽

Cox Proportional Hazards Model ◽

Altered Expression ◽

S100a4 Expression ◽

The Impact

Abstract Background Glucose metabolism transformation plays critical role in cancer cell malignancies maintenance. Aberrant cancer cell metabolism is considered to be the hallmark of cancer. S100A4 has been identified as an oncogene in a variety of cancers. However, its role in the cancer cell glucose reprogramming has been seldom reported. The aim of this study was to examine the role of S100A4 in aerobic glycolysis in colorectal cancer (CRC). Methods We investigated S100A4 expression in 224 cases of primary CRC and matched normal colonic tissue specimens, and explored the underlying mechanisms of altered S100A4 expression as well as the impact of this altered expression on CRC growth and glycolysis using in vitro and animal models of CRC. Results S100A4 was more highly expressed in CRC tissues than in the adjacent normal tissues (59.4% vs 17.4%, P <0.05). Higher S100A4 expression was associated with advanced node stage ( P =0.018) and larger tumor size ( P =0.035). A Cox proportional hazards model suggested that S100A4 expression was an independent prognostic factor for both OS (HR: 3.967, 95%CI: 1.919-8.200, P <0.001) and DFS (HR: 4.350, 95%CI: 2.264-8.358, P <0.001) in CRC after surgery. Experimentally, silencing S100A4 expression significantly decreased the growth and glycolysis rate of CRC both in vitro and in vivo . Mechanically, S100A4 could affect the hypoxia-inducible factor (HIF)-1α activity as demonstrated by the HIF-1α response element–luciferase activity in CRC cells. Conclusions These results disclose a novel role for S100A4 in reprogramming the metabolic process in CRC by affecting the HIF-1α activity and provide potential prognostic predictors for CRC.

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Delayed viral clearance and exacerbated airway hyperinflammation in hypertensive COVID-19 patients

10.1101/2020.09.22.20199471 ◽

2020 ◽

Author(s):

Saskia Trump ◽

Soeren Lukassen ◽

Markus S Anker ◽

Robert Lorenz Chua ◽

Johannes Liebig ◽

...

Keyword(s):

Cardiovascular Disease ◽

Immune Cell ◽

Angiotensin Receptor Blockers ◽

Treatment Options ◽

Angiotensin Converting Enzyme Inhibitors ◽

Sequencing Data ◽

Converting Enzyme Inhibitors ◽

Altered Expression ◽

The Impact

In COVID-19, hypertension and cardiovascular diseases have emerged as major risk factors for critical disease progression. Concurrently, the impact of the main anti-hypertensive therapies, angiotensin-converting enzyme inhibitors (ACEi) and angiotensin receptor blockers (ARB), on COVID-19 severity is controversially discussed. By combining clinical data, single-cell sequencing data of airway samples and in vitro experiments, we assessed the cellular and pathophysiological changes in COVID-19 driven by cardiovascular disease and its treatment options. Anti-hypertensive ACEi or ARB therapy, was not associated with an altered expression of SARS-CoV-2 entry receptor ACE2 in nasopharyngeal epithelial cells and thus presumably does not change susceptibility for SARS-CoV-2 infection. However, we observed a more critical progress in COVID-19 patients with hypertension associated with a distinct inflammatory predisposition of immune cells. While ACEi treatment was associated with dampened COVID-19-related hyperinflammation and intrinsic anti-viral responses, under ARB treatment enhanced epithelial-immune cell interactions were observed. Macrophages and neutrophils of COVID-19 patients with hypertension and cardiovascular comorbidities, in particular under ARB treatment, exhibited higher expression of CCL3, CCL4, and its receptor CCR1, which associated with critical COVID-19 progression. Overall, these results provide a potential explanation for the adverse COVID-19 course in patients with cardiovascular disease, i.e. an augmented immune response in critical cells for the disease course, and might suggest a beneficial effect of clinical ACEi treatment in hypertensive COVID-patients.

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Quantifying the impact of gut microbiota on inflammation and hypertensive organ damage

10.1101/2021.09.17.460671 ◽

2021 ◽

Author(s):

Elllen G Avery ◽

Hendrik Bartolomaeus ◽

Ariana Rauch ◽

Chia-Yu Chen ◽

Gabriele N'diaye ◽

...

Keyword(s):

Gut Microbiota ◽

Th17 Cells ◽

Suppressor Cells ◽

Short Chain Fatty Acids ◽

Organ Damage ◽

Microbial Colonization ◽

Cardiac Damage ◽

The Impact ◽

Colonization Status

Aims: Hypertension (HTN) can lead to heart and kidney damage. The gut microbiota has been linked to HTN, although it is difficult to estimate its significance due to the variety of other features known to influence HTN. Methods and Results: In the present study, we used germ-free (GF) and colonized (COL) littermate mice to quantify the impact of microbial colonization on organ damage in HTN. Four-week-old male GF C57BL/6J littermates were randomized to remain GF or receive microbial colonization. HTN was induced by subcutaneous infusion with angiotensin (Ang) II (1.44mg/kg/d) and 1% NaCl in the drinking water; sham-treated mice served as control. Renal damage was exacerbated in GF mice, whereas cardiac damage was more comparable between COL and GF, suggesting that the kidney is more sensitive to microbial influence. Multivariate analysis revealed a larger effect of HTN in GF mice. Serum metabolomics demonstrated that the colonization status influences circulating metabolites relevant to HTN. Importantly, GF mice were deficient in anti-inflammatory fecal short-chain fatty acids (SCFA). Flow cytometry showed that the microbiome has an impact on the induction of anti-hypertensive myeloid-derived suppressor cells and pro-inflammatory Th17 cells in HTN. In vitro inducibility of Th17 cells was significantly higher for cells isolated from GF than conventionally raised mice. Conclusion: Microbial colonization status of mice had potent effects on their phenotypic response to a hypertensive stimulus, and the kidney is a highly microbiota-susceptible target organ in HTN. The magnitude of the pathogenic response in GF mice underscores the role of the microbiome in mediating inflammation in HTN.

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Chlorogenic Acid Functions as a Novel Agonist of PPARγ2 during the Differentiation of Mouse 3T3-L1 Preadipocytes

BioMed Research International ◽

10.1155/2018/8594767 ◽

2018 ◽

Vol 2018 ◽

pp. 1-14 ◽

Cited By ~ 6

Author(s):

Shu-guang Peng ◽

Yi-lin Pang ◽

Qi Zhu ◽

Jing-he Kang ◽

Ming-xin Liu ◽

...

Keyword(s):

Chlorogenic Acid ◽

Fruits And Vegetables ◽

Quantitative Polymerase Chain Reaction ◽

Lipid Synthesis ◽

Peroxisome Proliferator ◽

Mrna Levels ◽

The Impact

Rosiglitazone (RG) is a well-known activator of peroxisome proliferator-activated receptor-gamma (PPARγ) and used to treat hyperglycemia and type 2 diabetes; however, its clinical application has been confounded by adverse side effects. Here, we assessed the roles of chlorogenic acid (CGA), a phenolic secondary metabolite found in many fruits and vegetables, on the differentiation and lipolysis of mouse 3T3-L1 preadipocytes. The results showed that CGA promoted differentiation in vitro according to oil red O staining and quantitative polymerase chain reaction assays. As a potential molecular mechanism, CGA downregulated mRNA levels of the adipocyte differentiation-inhibitor gene Pref1 and upregulated those of major adipogenic transcriptional factors (Cebpb and Srebp1). Additionally, CGA upregulated the expression of the differentiation-related transcriptional factor PPARγ2 at both the mRNA and protein levels. However, following CGA intervention, the accumulation of intracellular triacylglycerides following preadipocyte differentiation was significantly lower than that in the RG group. Consistent with this, our data indicated that CGA treatment significantly upregulated the expression of lipogenic pathway-related genes Plin and Srebp1 during the differentiation stage, although the influence of CGA was weaker than that of RG. Notably, CGA upregulated the expression of the lipolysis-related gene Hsl, whereas it did not increase the expression of the lipid synthesis-related gene Dgat1. These results demonstrated that CGA might function as a potential PPARγ agonist similar to RG; however, the impact of CGA on lipolysis in 3T3-L1 preadipocytes differed from that of RG.

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Gallic acid enhances reproductive function by modulating oxido-inflammatory and apoptosis mediators in rats exposed to aflatoxin-B1

Experimental Biology and Medicine ◽

10.1177/1535370220936206 ◽

2020 ◽

Vol 245 (12) ◽

pp. 1016-1028 ◽

Cited By ~ 2

Author(s):

Solomon E Owumi ◽

Isaac A Adedara ◽

Ayomide P Akomolafe ◽

Ebenezer O Farombi ◽

Adegboyega K Oyelere

Keyword(s):

Oxidative Stress ◽

Gallic Acid ◽

Aflatoxin B1 ◽

Reproductive Function ◽

Interleukin 10 ◽

Antioxidant Defenses ◽

The Impact ◽

Hormonal Levels

Aflatoxin B1 (AFB1) is reported to elicit adverse reproductive outcomes in animals. Gallic acid (GA) is known to exhibit antioxidant and inflammatory bioactivities. The impact of GA on AFB1-facilitated reproductive dysfunction is nonexistent in literature. This investigation elucidated GA protective effect on AFB1-induced reproductive toxicities in rats, exposed for 28 consecutive days to AFB1 (75 µg/kg), or co-treated with GA (20 or 40 mg/kg) body weight. AFB1 significantly (p < 0.05) reduced testicular function biomarkers, serum hormonal levels, and functional sperm characteristics in experimental animals. GA abated AFB1-induced increases (p < 0.05) in lipid peroxidation and reactive oxygen and nitrogen species, suppressed myeloperoxidase, interleukin-1β, nitric oxide, and tumor necrosis factor-α levels—inflammatory biomarkers—in testes, epididymis, and hypothalamus. Furthermore, GA improved antioxidant defenses and alleviated reduction in interleukin-10, caspase-3 activation, and histological variations in epididymis, testes, and hypothalamus of rats dosed with AFB1. Conclusively, GA enhanced reproductive function in AFB1-exposed rats by modulating inflammatory, oxidative stress, and apoptosis mediators. Impact statement Infertility resulting from reproductive deficiency can be stressful. Exposure to aflatoxin B1, a dietary mycotoxin prevalent in improperly stored grains, is reported to elicit reproductive insufficiencies and infertility. We, therefore, examined the likely beneficial effect of gallic acid (GA) a phytochemical, recognized to exhibit in vitro and in vivo pharmacological bioactivities against oxidative stress and related inflammatory damages in rats, since AFB1 toxicities are predicated on oxidative epoxide formation, in a bid to proffer new evidence to advance the field of nutriceutical application from plant-derived chemopreventive agents. Our findings will advance the field of chemoprevention by presenting data absent in the literature on GA. Our results demonstrate further evidence for GA conferred protection against AFB1-mediated histological lesions in testes, epididymis, and hypothalamus of treated rats; suppresses oxidative damages, relieved inflammatory and apoptotic responses, restored sperm functional characteristics, and hormonal levels relevant for reproductive integrity and function.

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