scholarly journals Explaining the unexpected COVID-19 trends and potential impact across Africa.

F1000Research ◽  
2021 ◽  
Vol 10 ◽  
pp. 1177
Author(s):  
Daniel Oduro-Mensah ◽  
Ebenezer Oduro-Mensah ◽  
Peter Quashie ◽  
Gordon Awandare ◽  
Laud Okine
Keyword(s):  
Immune Response ◽  
Central Africa ◽  
Mortality Rates ◽  
Low Grade ◽  
Innate Immune Responses ◽  
Two Factors ◽  
The Impact ◽  
Low Grade Inflammation ◽  
Frequent Exposure

Official COVID-19 case counts and mortality rates across Africa are lower than had been anticipated. Research reports, however, indicate far higher exposure rates than the official counts in some countries. Particularly in Western and Central Africa, where mortality rates are disproportionately lower than the rest of the continent, this occurrence may be due to immune response adaptations resulting from (1) frequent exposure to certain pro-inflammatory pathogens, and (2) a prevalence of low-grade inflammation coupled with peculiar modifications to the immune response based on one’s immunobiography. We suggest that the two factors lead to a situation where post infection, there is a rapid ramp-up of innate immune responses, enough to induce effective defense and protection against plethora pathogens. Alongside current efforts at procuring and distributing vaccines, we draw attention to the need for work towards appreciating the impact of the apparently widespread, asymptomatic SARS-CoV-2 infections on Africa’s populations vis a vis systemic inflammation status and long-term consequences for public health.

scholarly journals The Impact of Dietary Sphingolipids on Intestinal Microbiota and Gastrointestinal Immune Homeostasis

2021 ◽  
Vol 12 ◽  
Author(s):  
Johanna Rohrhofer ◽  
Benjamin Zwirzitz ◽  
Evelyne Selberherr ◽  
Eva Untersmayr
Keyword(s):  
Immune Response ◽  
Gut Microbiota ◽  
Intestinal Microbiota ◽  
Barrier Function ◽  
Intestinal Cell ◽  
Immune Homeostasis ◽  
Low Grade ◽  
Vast Number ◽  
The Impact ◽  
Low Grade Inflammation

The large surfaces of gastrointestinal (GI) organs are well adapted to their diverse tasks of selective nutritional uptake and defense against the external environment. To maintain a functional balance, a vast number of immune cells is located within the mucosa. A strictly regulated immune response is required to impede constant inflammation and to maintain barrier function. An increasing prevalence of GI diseases has been reported in Western societies over the past decades. This surge in GI disorders has been linked to dietary changes followed by an imbalance of the gut microbiome, leading to a chronic, low grade inflammation of the gut epithelium. To counteract the increasing health care costs associated with diseases, it is paramount to understand the mechanisms driving immuno-nutrition, the associations between nutritional compounds, the commensal gut microbiota, and the host immune response. Dietary compounds such as lipids, play a central role in GI barrier function. Bioactive sphingolipids (SLs), e.g. sphingomyelin (SM), sphingosine (Sph), ceramide (Cer), sphingosine-1- phosphate (S1P) and ceramide-1-phosphate (C1P) may derive from dietary SLs ingested through the diet. They are not only integral components of cell membranes, they additionally modulate cell trafficking and are precursors for mediators and second messenger molecules. By regulating intracellular calcium levels, cell motility, cell proliferation and apoptosis, SL metabolites have been described to influence GI immune homeostasis positively and detrimentally. Furthermore, dietary SLs are suggested to induce a shift in the gut microbiota. Modes of action range from competing with the commensal bacteria for intestinal cell attachment to prevention from pathogen invasion by regulating innate and immediate defense mechanisms. SL metabolites can also be produced by gut microorganisms, directly impacting host metabolic pathways. This review aims to summarize recent findings on SL signaling and functional variations of dietary SLs. We highlight novel insights in SL homeostasis and SL impact on GI barrier function, which is directly linked to changes of the intestinal microbiota. Knowledge gaps in current literature will be discussed to address questions relevant for understanding the pivotal role of dietary SLs on chronic, low grade inflammation and to define a balanced and healthy diet for disease prevention and treatment.

scholarly journals Consumption of Select Dietary Emulsifiers Exacerbates the Development of Spontaneous Intestinal Adenoma

2021 ◽  
Vol 22 (5) ◽  
pp. 2602
Author(s):  
Emilie Viennois ◽  
Benoit Chassaing
Keyword(s):  
Intestinal Inflammation ◽  
Tumor Development ◽  
Low Grade ◽  
Gastrointestinal Cancers ◽  
Cancer Initiation ◽  
And Function ◽  
The Impact ◽  
Chronic Intestinal Inflammation ◽  
Low Grade Inflammation ◽  
Intestinal Adenoma

Inflammation is a well-characterized critical driver of gastrointestinal cancers. Previous findings have shown that intestinal low-grade inflammation can be promoted by the consumption of select dietary emulsifiers, ubiquitous component of processed foods which alter the composition and function of the gut microbiota. Using a model of colitis-associated cancer, we previously reported that consumption of the dietary emulsifiers carboxymethylcellulose or polysorbate-80 exacerbated colonic tumor development. Here, we investigate the impact of dietary emulsifiers consumption on cancer initiation and progression in a genetical model of intestinal adenomas. In APCmin mice, we observed that dietary emulsifiers consumption enhanced small-intestine tumor development in a way that appeared to be independent of chronic intestinal inflammation but rather associated with emulsifiers’ impact on the proliferative status of the intestinal epithelium as well as on intestinal microbiota composition in both male and female mice. Overall, our findings further support the hypothesis that emulsifier consumption may be a new modifiable risk factor for colorectal cancer (CRC) and that alterations in host–microbiota interactions can favor gastrointestinal carcinogenesis in individuals with a genetical predisposition to such disorders.

The impact of Vaccination worldwide on SARS-CoV-2 infection: A Review on Vaccine Mechanisms, Results of Clinical Trials, Vaccinal Coverage and Interactions with Novel Variants

2021 ◽  
Vol 28 ◽  
Author(s):  
Douglas Henrique Pereira Damasceno ◽  
Arthur Aguiar Amaral ◽  
Cecília Andrade Silva ◽  
Ana Cristina Simões e Silva
Keyword(s):  
Immune Response ◽  
Clinical Trials ◽  
Placebo Group ◽  
Mechanisms Of Action ◽  
Novel Variants ◽  
The Impact ◽  
Positive Results ◽  
Epidemiological Information ◽  
Long Term Studies

Background: The COVID-19 pandemic demanded a global effort towards quickly developing safe and effective vaccines against SARS-CoV-2. Objective: This review aimed to discuss the main vaccines available, their mechanisms of action, results of clinical trials and epidemiological behavior. The implications of viral variants were also debated. Methods: A non-systematic literature review was performed between February and March 2021 by searching the Pubmed, Scopus, and SciELO databases, using different combinations of the following terms: "vaccines", "clinical trials" , "SARS-CoV-2", "Coronavirus", "COVID-19", "mechanisms of action". Data regarding clinical trials of SARS-CoV-2 vaccines and epidemiological information were also searched. Results: The mechanisms of action included vector-virus, mRNA and inactivated virus vaccines. The vaccines showed positive results in phases 2/3 clinical trials. The efficacy of the mRNA 1273 and of mRNA BNT 162b2 vaccines were 94.1% and 95%, respectively. The effectiveness of the ChAdOx1 nCoV-19 vaccine varied according to the scheme, with an overall value of 70.4%. The Gam-COVID-Vac vaccine had an efficacy of 91.6%. Regarding the Ad26.COV2.S vaccine, 99% or more of seroconversion was observed in all subgroups 29 days after vaccination. The CoronaVac vaccine induced an immune response in 92% of the volunteers receiving 3ug and in 98% with 6ug, in comparison to 3% in the placebo group. Conclusion: Global efforts have resulted in vaccines available in record time, with good safety and immunogenicity profile. However, only long-term studies can provide more information on duration of immunity and the need for additional doses.

Abstract 14849: Gender Differences in Impact of CYP2C19 Polymorphism and Low Grade Inflammation on Coronary Spasm in Patients with Vasospastic Angina (VSA)

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Tomonori Akasaka ◽  
Seiji Hokimoto ◽  
Noriaki Tabata ◽  
Kenji Sakamoto ◽  
Kenichi Tsujita ◽  
...  
Keyword(s):  
Coronary Artery ◽  
Coronary Artery Spasm ◽  
Coronary Spasm ◽  
Control Group ◽  
Low Grade ◽  
Cyp2c19 Genotype ◽  
Loss Of Function ◽  
Hs Crp ◽  
The Impact ◽  
Low Grade Inflammation

Background: Several cytochrome P450 (CYP) enzyme families have been identified in extra hepatic tissues such as heart, vasculature, kidney, and lung. CYP2C19 localized in vascular smooth muscle and endothelium contributes to the regulation of vascular tone and homeostasis. However, it is unknown whether CYP2C19 genotype is associated with the vascular tonus in patients with VSA. The aim of this study was to examine the impact of CYP2C19 genotype on coronary artery spasm in patients with VSA. Methods: We examined the distribution of CYP2C19 genotype in patients with VSA (n=129) who were diagnosed by intra-coronary acetylcholine infusion test and healthy subjects (n=455) as control group. CYP2C19 genotypes were divided into 3 groups; (1) CYP2C19*1/*1: EM, (2) one loss-of-function allele (*1/*2, *1/*3: IM), and (3) two loss-of-function alleles (*2/*2, *2/*3, *3/*3: PM). Moreover, we measured the level of high-sensitive CRP (hs-CRP) as a degree of low glade inflammation in each group. Results: The ratios of CYP2C19 genotype (EM, IM, and PM) were 30, 42, and 28% in VSA group, and 32, 49, and 19% in control group. In short, PM frequency was significantly higher in VSA than in control (28% vs 19%, P=0.026). In VSA group, the ratios of CYP2C19 genotype were 36, 44, and 20% in male, and 20, 39, and 41% in female, respectively. Briefly, the PM frequency was significantly higher in female than in male (41% vs 20%, P<0.001). Moreover, the level of hs-CRP was significantly higher in VSA group than in control group (0.17±0.367 vs 0.10.±0.240, P=0.02). When patients were stratified by gender, the level of hs-CRP was significantly higher in VSA group in female (0.11±0.198 vs 0.06±0.105, P=0.031) and male (0.20±0.438 vs 0.12±0.277, P=0.044). Multivariate analysis for coronary spasm indicated high age, hypertension, and high level of hs-CRP as predictive factors among all subjects. PM is a predictive factor for coronary spasm in female group only (OR3.1, 95%RI 1.525-6.317, P=0.002), but not in male (OR0.829, 95%RI 0.453-1.518, P=0.543). Conclusion: The CYP2C19 two loss-of-function alleles (PM) and low grade inflammation may be associated with pathophysiology of coronary artery spasm and the regulation of coronary tonus, especially in female.

scholarly journals Genetic polymorphisms mediating behavioural and immune response to pathogens may moderate the impact of the COVID-19 pandemic: a pilot study

2020 ◽  
Author(s):  
Ravi Philip Rajkumar
Keyword(s):  
Immune Response ◽  
Pilot Study ◽  
Immune Responses ◽  
Genetic Variants ◽  
Mortality Rates ◽  
Therapeutic Strategies ◽  
Published Data ◽  
Entire World ◽  
S Allele ◽  
The Impact

AbstractBackgroundThe COVID-19 pandemic has affected the entire world, but there are wide variations in prevalence and mortality across nations. Genetic variants which influence behavioural or immune responses to pathogens, selected for by pathogen pressure, may influence this variability. Two relevant polymorphisms in this context are the s allele of the serotonin transporter promoter (5-HTTLPR) and the G allele of the interleukin-6 gene (IL-6 rs1800795).MethodsThe frequencies of the 5-HTTLPR s allele and IL-6 rs1800795 G allele were obtained from published data. The correlations between these allele frequencies and the prevalence and mortality rates of COVID-19 were examined across 44 nations.ResultsThe IL-6 rs1800795 G allele was negatively correlated with COVID-19 prevalence (ρ = −0.466, p < 0.01) and mortality (ρ = −0.591, p<0.001) across nations. The 5-HTTLPR s allele was negatively correlated with COVID-19 mortality rates (ρ = −0.437, p = 0.023).ConclusionsThese results suggest that a significant relationship exists between genetic variants that influence behavioural and immune responses to pathogens and indices of the impact of COVID-19 across nations. Further investigation of these variants and their correlates may permit the development of better preventive or therapeutic strategies in the management of the COVID-19 pandemic.

scholarly journals Metabolic biomarker profiling for identification of susceptibility to severe pneumonia and COVID-19 in the general population

eLife ◽  
2021 ◽  
Vol 10 ◽  
Author(s):  
◽  
Heli Julkunen ◽  
Anna Cichońska ◽  
P Eline Slagboom ◽  
Peter Würtz
Keyword(s):  
General Population ◽  
Disease Onset ◽  
Severe Pneumonia ◽  
Blood Sampling ◽  
Low Grade ◽  
Healthy Individuals ◽  
Metabolic Biomarkers ◽  
Low Grade Inflammation ◽  
Increased Susceptibility

Biomarkers of low-grade inflammation have been associated with susceptibility to a severe infectious disease course, even when measured prior to disease onset. We investigated whether metabolic biomarkers measured by nuclear magnetic resonance (NMR) spectroscopy could be associated with susceptibility to severe pneumonia (2507 hospitalised or fatal cases) and severe COVID-19 (652 hospitalised cases) in 105,146 generally healthy individuals from UK Biobank, with blood samples collected 2007–2010. The overall signature of metabolic biomarker associations was similar for the risk of severe pneumonia and severe COVID-19. A multi-biomarker score, comprised of 25 proteins, fatty acids, amino acids and lipids, was associated equally strongly with enhanced susceptibility to severe COVID-19 (odds ratio 2.9 [95%CI 2.1–3.8] for highest vs lowest quintile) and severe pneumonia events occurring 7–11 years after blood sampling (2.6 [1.7–3.9]). However, the risk for severe pneumonia occurring during the first 2 years after blood sampling for people with elevated levels of the multi-biomarker score was over four times higher than for long-term risk (8.0 [4.1–15.6]). If these hypothesis generating findings on increased susceptibility to severe pneumonia during the first few years after blood sampling extend to severe COVID-19, metabolic biomarker profiling could potentially complement existing tools for identifying individuals at high risk. These results provide novel molecular understanding on how metabolic biomarkers reflect the susceptibility to severe COVID-19 and other infections in the general population.

Abstract 14862: Gender Differences in Impact of CYP2C19 Polymorphism and Low Grade Inflammation on Coronary Microvascular Disease

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Tomonori Akasaka ◽  
Seiji Hokimoto ◽  
Noriaki Tabata ◽  
Kenji Sakamoto ◽  
Kenichi Tsujita ◽  
...  
Keyword(s):  
Microvascular Disease ◽  
Control Group ◽  
Female Group ◽  
Low Grade ◽  
Cyp2c19 Genotype ◽  
Loss Of Function ◽  
Disease Group ◽  
Hs Crp ◽  
The Impact ◽  
Low Grade Inflammation

Background: Specific CYPs localized in vascular smooth muscle and endothelium contribute to the regulation of vascular tone and homeostasis. CYP2C19 two loss-of-function alleles (PM) were found to be an independent risk factor for diabetic retinopathy, and PM is associated with the coronary spasm especially in female. However, it is unknown whether CYP2C19 genotype is associated with the coronary microvascular disease. The aim was to evaluate the impact of CYP2C19 genotype on coronary microvascular disease. Methods: We examined CYP2C19 genotype in patients with microvascular disease (n=40) who were diagnosed by intra-coronary acetylcholine infusion test and healthy subjects (n=455) as control group. We defined the coronary microvascular disease that have no epicardial spasm and have angina, ischemic ECG changes, reduced coronary blood flow, or inversion of lactic acid level between intra-coronary and coronary sinus. CYP2C19 genotypes were divided into 3 groups; (1) CYP2C19*1/*1: EM, (2) one loss-of-function allele (*1/*2, *1/*3: IM), and (3) two loss-of-function alleles (*2/*2, *2/*3, *3/*3: PM). Results: The ratios of CYP2C19 genotype (EM, IM, and PM) were 33, 35, and 32% in microvascular disease group, and 32, 49, and 19% in control group. In short, PM frequency was significantly higher in microvascular disease group (32%vs19%,P=0.039). In microvascular disease group, the ratios of CYP2C19 genotype (EM, IM, and PM) were 44, 38, and 19% in male, and 25, 33, and 42% in female, respectively. Briefly, the PM frequency was significantly higher in female than in male (42%vs19%,P=0.011). Moreover, the level of hs-CRP was significantly higher in microvascular disease group (0.37±0.908 vs 0.10±0.240, P<0.001). Multivariate analysis for microvascular disease indicated that gender, high age, smoking, hypertension, and the high level of hs-CRP are predictive factors among all subjects. PM is a predictive factor for microvascular disease in female group only (OR3.214, 95%RI 1.286-8.034, P=0.012), but not in male (OR0.909, 95%RI 0.251-3.285, P=0.884). Conclusion: The CYP2C19 two loss-of-function alleles (PM) and low grade inflammation may be associated with pathophysiology of coronary microvascular disease, especially in female.

scholarly journals Intestinal Explant Cultures from Gilthead Seabream (Sparus aurata, L.) Allowed the Determination of Mucosal Sensitivity to Bacterial Pathogens and the Impact of a Plant Protein Diet

2020 ◽  
Vol 21 (20) ◽  
pp. 7584
Author(s):  
David Sánchez Peñaranda ◽  
Christine Bäuerl ◽  
Ana Tomás-Vidal ◽  
Miguel Jover-Cerdá ◽  
Guillem Estruch ◽  
...  
Keyword(s):  
Immune Response ◽  
Phase Ii ◽  
Plant Protein ◽  
Gilthead Seabream ◽  
Growth Stages ◽  
Short Term ◽  
Short Term Exposure ◽  
Cox 2 ◽  
The Impact

The interaction between diet and intestinal health has been widely discussed, although in vivo approaches have reported limitations. The intestine explant culture system developed provides an advantage since it reduces the number of experimental fish and increases the time of incubation compared to similar methods, becoming a valuable tool in the study of the interactions between pathogenic bacteria, rearing conditions, or dietary components and fish gut immune response. The objective of this study was to determine the influence of the total substitution of fish meal by plants on the immune intestinal status of seabream using an ex vivo bacterial challenge. For this aim, two growth stages of fish were assayed (12 g): phase I (90 days), up to 68 g, and phase II (305 days), up to 250 g. Additionally, in phase II, the effects of long term and short term exposure (15 days) to a plant protein (PP) diet were determined. PP diet altered the mucosal immune homeostasis, the younger fish being more sensitive, and the intestine from fish fed short-term plant diets showed a higher immune response than with long-term feeding. Vibrio alginolyticus (V. alginolyticus) triggered the highest immune and inflammatory response, while COX-2 expression was significantly induced by Photobacterium damselae subsp. Piscicida (P. damselae subsp. Piscicida), showing a positive high correlation between the pro-inflammatory genes encoding interleukin 1β (IL1-β), interleukin 6 (IL-6) and cyclooxygenase 2(COX-2).

scholarly journals Multiplex Bead Array Assay of a Panel of Circulating Cytokines and Growth Factors in Patients with Albuminuric and Non-Albuminuric Diabetic Kidney Disease

2020 ◽  
Vol 9 (9) ◽  
pp. 3006
Author(s):  
Vadim V. Klimontov ◽  
Anton I. Korbut ◽  
Nikolai B. Orlov ◽  
Maksim V. Dashkin ◽  
Vladimir I. Konenkov
Keyword(s):  
Growth Factors ◽  
Kidney Disease ◽  
Low Grade ◽  
Hs Crp ◽  
Low Grade Inflammation ◽  
Egfr Decline ◽  
Multiplex Bead ◽  
Circulating Cytokines

A panel of cytokines and growth factors, mediating low-grade inflammation and fibrosis, was assessed in patients with type 2 diabetes (T2D) and different patterns of chronic kidney disease (CKD). Patients with long-term T2D (N = 130) were classified into four groups: no signs of CKD; estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2 without albuminuria; albuminuria and eGFR ≥60 mL/min/1.73 m2; albuminuria and eGFR <60 mL/min/1.73 m2. Thirty healthy subjects were acted as control. Twenty-seven cytokines and growth factors were assessed in serum by multiplex bead array assay. Serum hs-CRP, urinary nephrin, podocine, and WFDC2 were measured by ELISA. Patients with T2D showed elevated IL-1Ra, IL-6, IL-17A, G-CSF, IP-10, MIP-1α, and bFGF levels; concentrations of IL-4, IL-12, IL-15, INF-γ, and VEGF were decreased. IL-6, IL-17A, G-CSF, MIP-1α, and bFGF correlated negatively with eGFR; IL-10 and VEGF demonstrated negative associations with WFDC2; no relationships with podocyte markers were found. Adjusted IL-17A and MIP-1α were predictors of non-albuminuric CKD, IL-13 predicted albuminuria with preserved renal function, meanwhile, IL-6 and hsCRP were predictors of albuminuria with eGFR decline. Therefore, albuminuric and non-albuminuric CKD in T2D patients are associated with different pro-inflammatory shifts in the panel of circulating cytokines.

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