Metabolic syndrome and aberrant immune responses to viral infection and vaccination: Insights from small animal models

Comparison of Metabolic Syndrome, Autoimmune and Viral Distinctive Inflammatory Related Conditions as Affected by Body Mass Index

Background: Metabolic inflammation (MI), long COVID (LC) and systemic lupus erythematosus (SLE) share some metabolic common manifestations and inflammatory pathophysiological similarities. Health-related quality of life (HRQoL) and metabolic age are indicators of health status. The "METAINFLAMMATION-CM Y2020/BIO-6600" project, a prospective controlled study, aimed to identify differential diagnostic tools and clinical features among three inflammatory conditions by comparing obesity status (low BMI vs. high BMI). Methods: A total of 272 adults of both Caucasian and Hispanic descent, diagnosed with MI, LC or SLE, and a range of BMI, were recruited. Clinical and phenotypic traits were measured to analyze body composition, metabolic and inflammatory markers, HRQoL data, metabolic age and lifestyle habits using a 3 × 2 (disease × BMI) factorial design. Results: Some inflammatory related variables, such as fibrinogen, RDW (red cell blood distribution width), ESR (erythrocyte sedimentation rate) and NLR (neutrophil/lymphocyte ratio), showed effect modifications depending on the BMI and disease type. In relation to HRQoL, the Physical Component Summary (PCS12) showed no relevant changes, while the Mental Component Summary (MCS12) showed a significant effect modification according to the disease type and BMI (p < 0.05). Furthermore, a significant interaction was identified between the disease type and BMI in relation to metabolic age (p = 0.02). Conclusions: Assessing the impact of BMI on these three inflammatory diseases may help to prevent clinical complications and to design personalized treatments, especially for patients with SLE, who have a worse prognosis with an increased BMI compared to the other two inflammatory diseases.

A Systematic Review of Metabolic Syndrome: Key Correlated Pathologies and Non-Invasive Diagnostic Approaches

Background and Objectives: Metabolic syndrome (MetS) is a condition marked by a complex array of physiological, biochemical, and metabolic abnormalities, including central obesity, insulin resistance, high blood pressure, and dyslipidemia (characterized by elevated triglycerides and reduced levels of high-density lipoproteins). The pathogenesis develops from the accumulation of lipid droplets in the hepatocyte (steatosis). This accumulation, in genetically predisposed subjects and with other external stimuli (intestinal dysbiosis, high caloric diet, physical inactivity, stress), activates the production of pro-inflammatory molecules, alter autophagy, and turn on the activity of hepatic stellate cells (HSCs), provoking the low grade chronic inflammation and the fibrosis. This syndrome is associated with a significantly increased risk of developing type 2 diabetes mellitus (T2D), cardiovascular diseases (CVD), vascular, renal, pneumologic, rheumatological, sexual, cutaneous syndromes and overall mortality, with the risk rising five- to seven-fold for T2DM, three-fold for CVD, and one and a half-fold for all-cause mortality. The purpose of this narrative review is to examine metabolic syndrome as a "systemic disease" and its interaction with major internal medicine conditions such as CVD, diabetes, renal failure, and respiratory failure. It is essential for internal medicine practitioners to approach this widespread condition in a "holistic" rather than a fragmented manner, particularly in Western countries. Additionally, it is important to be aware of the non-invasive tools available for assessing this condition. Materials and Methods: We conducted an exhaustive search on PubMed up to July 2024, focusing on terms related to metabolic syndrome and other pathologies (heart, Lung (COPD, asthma, pulmonary hypertension, OSAS) and kidney failure, vascular, rheumatological (osteoarthritis, rheumatoid arthritis), endocrinological, sexual pathologies and neoplastic risks. The review was managed in accordance with the PRISMA statement. Finally, we selected 300 studies (233 papers for the first search strategy and 67 for the second one). Our review included studies that provided insights into metabolic syndrome and non-invasive techniques for evaluating liver fibrosis and steatosis. Studies that were not conducted on humans, were published in languages other than English, or did not assess changes related to heart failure were excluded. Results: The findings revealed a clear correlation between metabolic syndrome and all the pathologies above described, indicating that non-invasive assessments of hepatic fibrosis and steatosis could potentially serve as markers for the severity and progression of the diseases. Conclusions: Metabolic syndrome is a multisystem disorder that impacts organs beyond the liver and disrupts the functioning of various organs. Notably, it is linked to a higher incidence of cardiovascular diseases, independent of traditional cardiovascular risk factors. Non-invasive assessments of hepatic fibrosis and fibrosis allow clinicians to evaluate cardiovascular risk. Additionally, the ability to assess liver steatosis may open new diagnostic, therapeutic, and prognostic avenues for managing metabolic syndrome and its complications, particularly cardiovascular disease, which is the leading cause of death in these patients.

Systems vaccinology studies - achievements and future potential

Human immune responses to vaccination are variable both within and between populations. Systems vaccinology, which is the application of multi-omics technologies to vaccine studies, seeks to understand such variation and predict responses to optimise vaccine strategies. Here, we outline new approaches to systems vaccinology, focusing on the incorporation of additional cohorts, endpoints and technologies.

Causal effect of lifestyle and metabolic indicator with herpes zoster: a two-sample Mendelian randomization study

Background

Previous observational studies have reported certain causal relationships between factors such as smoking, alcohol consumption, obesity, physical activity, metabolic disorders, and the incidence of herpes zoster (HZ). However, there is controversy regarding the observed results across different studies. Our objective was to investigate the causal effects of these risk factors on the risk of herpes zoster through a Mendelian randomization analysis using two-sample bidirectional approaches.

Methods

We conducted two-sample bidirectional Mendelian randomization analyses to explore the causal relationships between different lifestyles, obesity assessment indices, metabolic indicators, and the risk of herpes zoster. All exposure and outcome data were sourced from publicly available data from genome-wide association studies.

Results

In the inverse-variance weighted (IVW) analysis, body mass index (BMI) (OR: 1.160, 95% CI: 1.030-1.307, p = 0.014), Body fat percentage (BFP) (OR: 1.241, 95% CI: 1.050-1.467, p = 0.011), and whole body fat mass (WBFM) (OR: 1.199, 95% CI: 1.057-1.362, p = 0.005) exhibited positive associations with the risk of HZ. However, usual walking pace (UWP) (OR: 0.498, 95% CI: 0.254-0.976, p = 0.042) demonstrated a significant negative correlation with HZ risk. Other factors including alcohol intake frequency, smoking initiation, smoking status, insomnia, and sleep duration did not show significant causal relationships with HZ.

Conclusion

Mendelian randomization studies revealed that BMI, BFP, and WBFM are risk factors for HZ. UWP showed a protective effect against HZ. These findings provide a straightforward method for evaluating future clinical practices aiming to develop personalized management strategies and assess high-risk populations for HZ.

Efficacy, immunogenicity, and safety of COVID-19 vaccines in individuals with liver cirrhosis: a rapid review and meta-analysis

The emergence of coronavirus disease 2019 (COVID-19) vaccines has been a remarkable advancement. However, the efficacy, immunogenicity, and safety of these vaccines in individuals with liver cirrhosis require careful evaluation due to their compromised immune status and potential interactions with underlying liver disease. The present study aimed to evaluate the safety and efficacy of COVID-19 vaccines in liver cirrhosis patients. In the present study, we searched international databases, including Google Scholar, PubMed, Scopus, Embase, and Web of Science. The search strategy was carried out by using keywords and MeSH (Medical Subject Headings) terms. STATA ver. 15.0 (Stata Corp., USA) was used to analyze the data statistically. The analysis was performed using the random-effects model. We also used the chi-square test and I2 index to calculate heterogeneity among studies. For evaluating publication bias, Begg's funnel plots and Egger's tests were used. A total of 4,831 liver cirrhosis patients with COVID-19 were examined from 11 studies. The rate of hospitalization in the patients with liver cirrhosis was 17.6% (95% confidence interval [CI], 9%-44%). The rate of fever in the patients with liver cirrhosis was 4.5% (95% CI, 0.9%-8.1%). The rate of positive neutralizing antibodies in the patients with liver cirrhosis was 82.5% (95% CI, 69.8%-95.1%). Also, the rates of seroconversion after the second vaccination in patients with liver cirrhosis and the control group were 96.6% (95% CI, 92.0%-99.0%), and 99.7% (95% CI, 99.0%-100.0%), respectively. COVID-19 vaccines have demonstrated promising efficacy, immunogenicity, and safety profiles in individuals with liver cirrhosis, providing crucial protection against COVID-19-related complications.

The Metabolic Syndrome, a Human Disease

This review focuses on the question of metabolic syndrome (MS) being a complex, but essentially monophyletic, galaxy of associated diseases/disorders, or just a syndrome of related but rather independent pathologies. The human nature of MS (its exceptionality in Nature and its close interdependence with human action and evolution) is presented and discussed. The text also describes the close interdependence of its components, with special emphasis on the description of their interrelations (including their syndromic development and recruitment), as well as their consequences upon energy handling and partition. The main theories on MS's origin and development are presented in relation to hepatic steatosis, type 2 diabetes, and obesity, but encompass most of the MS components described so far. The differential effects of sex and its biological consequences are considered under the light of human social needs and evolution, which are also directly related to MS epidemiology, severity, and relations with senescence. The triggering and maintenance factors of MS are discussed, with especial emphasis on inflammation, a complex process affecting different levels of organization and which is a critical element for MS development. Inflammation is also related to the operation of connective tissue (including the adipose organ) and the widely studied and acknowledged influence of diet. The role of diet composition, including the transcendence of the anaplerotic maintenance of the Krebs cycle from dietary amino acid supply (and its timing), is developed in the context of testosterone and β-estradiol control of the insulin-glycaemia hepatic core system of carbohydrate-triacylglycerol energy handling. The high probability of MS acting as a unique complex biological control system (essentially monophyletic) is presented, together with additional perspectives/considerations on the treatment of this 'very' human disease.

T Cells in Tick-Borne Flavivirus Encephalitis: A Review of Current Paradigms in Protection and Disease Pathology

The family Flaviviridae is comprised of a diverse group of arthropod-borne viruses that are the etiological agents of globally relevant diseases in humans. Among these, infection with several of these flaviviruses-including West Nile virus (WNV), Zika virus (ZIKV), Japanese encephalitis virus (JEV), tick-borne encephalitis virus (TBEV), and Powassan virus (POWV)-can result in neuroinvasive disease presenting as meningitis or encephalitis. Factors contributing to the development and resolution of tick-borne flavivirus (TBEV, POWV) infection and neuropathology remain unclear, though many recently undertaken studies have described the virus-host interactions underlying encephalitic disease. With access to neural tissues despite the selectively permeable blood-brain barrier, T cells have emerged as one notable contributor to neuroinflammation. The goal of this review is to summarize the recent advances in tick-borne flavivirus immunology-particularly with respect to T cells-as it pertains to the development of encephalitis. We found that although T cell responses are rarely evaluated in a clinical setting, they are integral in conjunction with antibody responses to restricting the entry of TBFV into the CNS. The extent and means by which they can drive immune pathology, however, merits further study. Understanding the role of the T cell compartment in tick-borne flavivirus encephalitis is instrumental for improving vaccine safety and efficacy, and has implications for treatments and interventions for human disease.