Rami Salim Najjar

Dr. Rami Salim Najjar

Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia, USA
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Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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25 March 2018 in Clinical Cardiology
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Rami Salim NajjarRami Salim Najjar
Rami Salim Najjar
CMCarolyn E. Moore
Carolyn E. Moore
BMBaxter D. Montgomery
Baxter D. Montgomery

8 November 2019 in Nutrients
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Journal Article
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Rami Salim NajjarRami Salim Najjar
Rami Salim Najjar
Rafaela FeresinRafaela Feresin
Rafaela Feresin
Obesity affects over one-third of Americans and increases the risk of cardiovascular disease and type II diabetes. Interventional trials have consistently demonstrated that consumption of plant-based diets reduces body fat in overweight and obese subjects, even when controlling for energy intake. Nonetheless, the mechanisms underlying this effect have not been well-defined. This review discusses six major dietary mechanisms that may lead to reduced body fat. These include (1) reduced caloric density, (2) improved gut microbiota symbiosis, (3) increased insulin sensitivity, (4) reduced trimethylamine-N-oxide (TMAO), (5) activation of peroxisome proliferator-activated receptors (PPARs), and (6) over-expression of mitochondrial uncoupling proteins. Collectively, these factors improve satiety and increase energy expenditure leading to reduced body weight.

17 August 2018 in Clinical Cardiology
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Rami Salim NajjarRami Salim Najjar
Rami Salim Najjar
CMCarolyn E Moore
Carolyn E Moore
BMBaxter Delworth Montgomery
Baxter Delworth Montgomery
Background: Lipoprotein(a) [Lp(a)] is a highly atherogenic lipoprotein and is minimally effected by lifestyle changes. While some drugs can reduce Lp(a), diet has not consistently shown definitive reduction of this biomarker. The effect of consuming a plant‐based diet on serum Lp(a) concentrations have not been previously evaluated.Hypothesis: Consumption of a defined, plant‐based for 4 weeks reduces Lp(a).Methods: Secondary analysis of a previous trial was conducted, in which overweight and obese individuals (n = 31) with low‐density lipoprotein cholesterol concentrations >100 mg/dL consumed a defined, plant‐based diet for 4 weeks. Baseline and 4‐week labs were collected. Data were analyzed using a paired samples t‐test.Results: Significant reductions were observed for serum Lp(a) (−32.0 ± 52.3 nmol/L, P = 0.003), apolipoprotein B (−13.2 ± 18.3 mg/dL, P < 0.0005), low‐density lipoprotein (LDL) particles (−304.8 ± 363.0 nmol/L, P < 0.0005) and small‐dense LDL cholesterol (−10.0 ± 9.2 mg/dL, P < 0.0005). Additionally, serum interleukin‐6 (IL‐6), total white blood cells, lipoprotein‐associated phospholipase A2 (Lp‐PLA2), high‐sensitivity c‐reactive protein (hs‐CRP), and fibrinogen were significantly reduced (P ≤ 0.004).Conclusions: A defined, plant‐based diet has a favorable impact on Lp(a), inflammatory indicators, and other atherogenic lipoproteins and particles. Lp(a) concentration was previously thought to be only minimally altered by dietary interventions. In this protocol however, a defined plant‐based diet was shown to substantially reduce this biomarker. Further investigation is required to elucidate the specific mechanisms that contribute to the reductions in Lp(a) concentrations, which may include alterations in gene expression.

Verified
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Rami Salim NajjarRami Salim Najjar
Rami Salim Najjar
Rafaela FeresinRafaela Feresin
Rafaela Feresin
Heart failure (HF) is a leading cause of death in the United States, with a 5-year mortality rate of 50% despite modern pharmacological therapies. Plant-based diets are comprised of a diverse polyphenol profile, which lends to their association with reduced cardiovascular disease risk. Whether a polyphenol-rich diet can slow the progression of or reverse HF in humans is not known. To date, in vitro and in vivo studies have reported on the protective role of polyphenols in HF. In this review, we will discuss the major mechanisms by which polyphenols mitigate HF in vitro and in vivo, including (1) reduced cardiac inflammation and oxidative stress, (2) reduced mitochondrial dysfunction, (3) improved Ca2+ homeostasis, (4) increased survival signaling, and (5) increased sirtuin 1 activity.

27 January 2021 in Nutrients
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Rami Salim NajjarRami Salim Najjar
Rami Salim Najjar
Casey TurnerCasey Turner
Casey Turner
BWBrett Wong
Brett Wong
Rafaela FeresinRafaela Feresin
Rafaela Feresin
Cardiovascular disease (CVD) prevalence, pathogenesis, and manifestation is differentially influenced by biological sex. Berry polyphenols target several signaling pathways pertinent to CVD development, including inflammation, oxidative stress, and cardiac and vascular remodeling, and there are innate differences in these pathways that also vary by sex. There is limited research systematically investigating sex differences in berry polyphenol effects on these pathways, but there are fundamental findings at this time that suggest a sex-specific effect. This review will detail mechanisms within these pathological pathways, how they differ by sex, and how they may be individually targeted by berry polyphenols in a sex-specific manner. Because of the substantial polyphenolic profile of berries, berry consumption represents a promising interventional tool in the treatment and prevention of CVD in both sexes, but the mechanisms in which they function within each sex may vary.

23 March 2022 in Antioxidants
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Journal Article
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Rami Salim NajjarRami Salim Najjar
Rami Salim Najjar
Shengyu MuShengyu Mu
Shengyu Mu
Rafaela FeresinRafaela Feresin
Rafaela Feresin
Accumulating evidence indicate that blueberries have anti-hypertensive properties, which may be mainly due to its rich polyphenol content and their high antioxidant capacity. Thus, we aimed to investigate the mechanisms by which blueberry polyphenols exert these effects. Human aortic endothelial cells (HAECs) were incubated with 200 µg/mL blueberry polyphenol extract (BPE) for 1 h prior to a 12 h treatment with angiotensin (Ang) II, a potent vasoconstrictor. Our results indicate that Ang II increased levels of superoxide anions and decreased NO levels in HAECs. These effects were attenuated by pre-treatment with BPE. Ang II increased the expression of the pro-oxidant enzyme NOX1, which was not attenuated by BPE. Pre-treatment with BPE attenuated the Ang II-induced increase in the phosphorylation of the redox-sensitive MAPK kinases, SAPK/JNK and p38. BPE increased the expression of the redox-transcription factor NRF2 as well as detoxifying and antioxidant enzymes it transcribes including HO-1, NQO1, and SOD1. We also show that BPE attenuates the Ang II-induced phosphorylation of the NF-κB p65 subunit. Further, we show that inhibition of NRF2 leads to a decrease in the expression of HO-1 and increased phosphorylation of the NF-κB p65 subunit in HAECs treated with BPE and Ang II. These findings indicate that BPE acts through a NRF2-dependent mechanism to reduce oxidative stress and increase NO levels in Ang II-treated HAECs.