Protective regulation of the ACE2/ACE gene expression by estrogen in human atrial tissue from elderly men

Comparison of IgG Against COVID-19 Between Postmenopausal and Nonmenopausal Women Vaccinated With Sinopharm Vaccine

OBJECTIVE

Since December 2019, the coronavirus disease has spread among the people of the world. Past studies have shown that viral diseases are more common and the immune response is stronger among menopausal women than nonmenopausal women. Therefore, in this study, we aimed to compare the amount of immunoglobulin (Ig)G against COVID-19 between postmenopausal and nonmenopausal women vaccinated with Sinopharm vaccine.

METHODS

In this case-control study, 90 females vaccinated with the Sinopharm vaccine were randomly selected from February to April 2022: 45 menopausal participants as the case group and 45 nonmenopausal controls. Demographic characteristics were obtained and blood samples were taken from all subjects. A complete blood count was carried out and the levels of IgG against COVID-19 were measured by using the enzyme-linked immunosorbent assay method.

RESULTS

The mean age was 33.3 ± 7.3 years and 60.2 ± 7.02 years for control and menopausal women, respectively. A significant difference was found between the 2 groups for the levels of IgG antibodies against COVID-19 (P = .002, 17.2 ± 9.83 relative unit for case group and 10.2 ± 9.80 relative unit for control subjects). After adjusting, IgG against COVID-19 was significantly correlated to the menopausal state (odds ratio [confidence interval] = 1. 08 [1.03-1. 15]; P = .003).

CONCLUSION

The results of this study showed that menopausal women had higher levels of IgG against COVID-19 in comparison with nonmenopausal females. However, more complementary studies are needed in this regard.

Sex Differences among Overweight/Obese Kidney Transplant Recipients Requiring Oxygen Support Amid the COVID-19 Pandemic

Background and Objectives: Overweight/obesity puts individuals at greater risk for COVID-19 progression and mortality. We aimed to evaluate the impact of overweight/obesity on oxygen (O2) requirement outcomes of male and female kidney transplant recipients (KTRs) during the COVID-19 pandemic. Materials and Methods: We conducted a retrospective analysis of a cohort of KTRs diagnosed with COVID-19. Participants were stratified based on BMI categories, and data on the need for O2 therapy outcome were collected and analyzed separately for male and female KTRs. Results: In total, 284 KTRs (97 males and 187 females) were included in the study. Overweight/obesity was observed in 60.6% of male KTRs and 71% of female KTRs. Strikingly, overweight/obese women had a significantly higher requirement for supplemental O2 (63.3% vs. 41.7%, OR = 2.45, p = 0.03), particularly among older individuals (OR = 1.05, p = 0.04), smokers (OR = 4.55, p = 0.03), those with elevated lactate dehydrogenase (LDH) levels (OR = 1.01, p = 0.006), and those with lower admission and basal estimated glomerular filtration rate (eGFR) levels. Within this cohort, the necessity for O2 supplementation was correlated with more unfavorable outcomes. These included heightened mortality rates, transfers to the intensive care unit, employment of invasive mechanical ventilation, and the emergence of acute kidney injury requiring hemodialysis. On the other hand, although overweight/obese male KTRs had a higher prevalence of hypertension and higher fasting blood glucose levels, no significant association was found with COVID-19-related outcomes when compared to lean male KTRs. Conclusions: Overweight/obesity is highly prevalent in KTRs, and overweight/obese women demonstrated a higher need for supplemental O2. Therefore, the early identification of factors that predict a worse outcome in overweight/obese female KTRs affected by COVID-19 contributes to risk stratification and guides therapeutic decisions.

ACE2 in chronic disease and COVID-19: gene regulation and post-translational modification

Angiotensin-converting enzyme 2 (ACE2), a counter regulator of the renin-angiotensin system, provides protection against several chronic diseases. Besides chronic diseases, ACE2 is the host receptor for SARS-CoV or SARS-CoV-2 virus, mediating the first step of virus infection. ACE2 levels are regulated by transcriptional, post-transcriptional, and post-translational regulation or modification. ACE2 transcription is enhanced by transcription factors including Ikaros, HNFs, GATA6, STAT3 or SIRT1, whereas ACE2 transcription is reduced by the transcription factor Brg1-FoxM1 complex or ERRα. ACE2 levels are also regulated by histone modification or miRNA-induced destabilization. The protein kinase AMPK, CK1α, or MAP4K3 phosphorylates ACE2 protein and induces ACE2 protein levels by decreasing its ubiquitination. The ubiquitination of ACE2 is induced by the E3 ubiquitin ligase MDM2 or UBR4 and decreased by the deubiquitinase UCHL1 or USP50. ACE2 protein levels are also increased by the E3 ligase PIAS4-mediated SUMOylation or the methyltransferase PRMT5-mediated ACE2 methylation, whereas ACE2 protein levels are decreased by AP2-mediated lysosomal degradation. ACE2 is downregulated in several human chronic diseases like diabetes, hypertension, or lung injury. In contrast, SARS-CoV-2 upregulates ACE2 levels, enhancing host cell susceptibility to virus infection. Moreover, soluble ACE2 protein and exosomal ACE2 protein facilitate SARS-CoV-2 infection into host cells. In this review, we summarize the gene regulation and post-translational modification of ACE2 in chronic disease and COVID-19. Understanding the regulation and modification of ACE2 may help to develop prevention or treatment strategies for ACE2-mediated diseases.

Female mice are protected from impaired parenchymal arteriolar TRPV4 function and impaired cognition in hypertension

Hypertension is a leading modifiable risk factor for cerebral small vessel disease. Our laboratory has shown that endothelium-dependent dilation in cerebral parenchymal arterioles (PAs) is dependent on transient receptor potential vanilloid 4 (TRPV4) activation, and this pathway is impaired in hypertension. This impaired dilation is associated with cognitive deficits and neuroinflammation. Epidemiological evidence suggests that women with midlife hypertension have an increased dementia risk that does not exist in age-matched men, though the mechanisms responsible for this are unclear. This study aimed to determine the sex differences in young, hypertensive mice to serve as a foundation for future determination of sex differences at midlife. We tested the hypothesis that young hypertensive female mice would be protected from the impaired TRPV4-mediated PA dilation and cognitive dysfunction observed in male mice. Angiotensin II (ANG II)-filled osmotic minipumps (800 ng/kg/min, 4 wk) were implanted in 16- to 19-wk-old male C56BL/6 mice. Age-matched female mice received either 800 ng/kg/min or 1,200 ng/kg/min ANG II. Sham-operated mice served as controls. Systolic blood pressure was elevated in ANG II-treated male mice and in 1,200 ng ANG II-treated female mice versus sex-matched shams. PA dilation in response to the TRPV4 agonist GSK1016790A (10-9-10-5 M) was impaired in hypertensive male mice, which was associated with cognitive dysfunction and neuroinflammation, reproducing our previous findings. Hypertensive female mice exhibited normal TRPV4-mediated PA dilation and were cognitively intact. Female mice also showed fewer signs of neuroinflammation than male mice. Determining the sex differences in cerebrovascular health in hypertension is critical for developing effective therapeutic strategies for women.NEW & NOTEWORTHY Vascular dementia is a significant public health concern, and the effect of biological sex on dementia development is not well understood. TRPV4 channels are essential regulators of cerebral parenchymal arteriolar function and cognition. Hypertension impairs TRPV4-mediated dilation and memory in male rodents. Data presented here suggest female sex protects against impaired TRPV4 dilation and cognitive dysfunction during hypertension. These data advance our understanding of the influence of biological sex on cerebrovascular health in hypertension.

Impact of COVID-19 on the cardiovascular health of women: a review by the Italian Society of Cardiology Working Group on 'gender cardiovascular diseases'

The coronavirus disease 19 (COVID-19), due to coronavirus 2 (SARS-CoV-2) infection, presents with an extremely heterogeneous spectrum of symptoms and signs. COVID-19 susceptibility and mortality show a significant sex imbalance, with men being more prone to infection and showing a higher rate of hospitalization and mortality than women. In particular, cardiovascular diseases (preexistent or arising upon infection) play a central role in COVID-19 outcomes, differently in men and women. This review will discuss the potential mechanisms accounting for sex/gender influence in vulnerability to COVID-19. Such variability can be ascribed to both sex-related biological factors and sex-related behavioural traits. Sex differences in cardiovascular disease and COVID-19 involve the endothelial dysfunction, the innate immune system and the renin-angiotensin system (RAS). Furthermore, the angiotensin-converting enzyme 2 (ACE2) is involved in disease pathogenesis in cardiovascular disease and COVID-19 and it shows hormone-dependent actions. The incidence of myocardial injury during COVID-19 is sex-dependent, predominantly in association with a greater degree of inflammation and coagulation disorders among men. Its pathogenesis is not fully elucidated, but the main theories foresee a direct role for the ACE2 receptor, the hyperimmune response and the RAS imbalance, which may also lead to isolated presentation of COVID-19-mediated myopericarditis. Moreover, the latest evidence on cardiovascular diseases and their relationship with COVID-19 during pregnancy will be discussed. Finally, authors will analyse the prevalence of the long-covid syndrome between the two sexes and its impact on the quality of life and cardiovascular health.

Sexual Dimorphism in the Expression of Cardiac and Hippocampal Renin-Angiotensin and Kallikrein–Kinin Systems in Offspring from Mice Exposed to Alcohol during Gestation

Prenatal alcohol exposure (PAE) impairs fetal development. Alcohol consumption was shown to modulate the renin–angiotensin system (RAS). This study aimed to analyze the effects of PAE on the expression of the renin–angiotensin system (RAS) and kallikrein–kinin system (KKS) peptide systems in the hippocampus and heart of mice of both sexes. C57Bl/6 mice were exposed to alcohol during pregnancy at a concentration of 10% (v/v). On postnatal day 45 (PN45), mouse hippocampi and left ventricles (LV) were collected and processed for messenger RNA (mRNA) expression of components of the RAS and KKS. In PAE animals, more pronounced expression of AT1 and ACE mRNAs in males and a restored AT2 mRNA expression in females were observed in both tissues. In LV, increased AT2, ACE2, and B2 mRNA expressions were also observed in PAE females. Furthermore, high levels of H2O2 were observed in males from the PAE group in both tissues. Taken together, our results suggest that modulation of the expression of these peptidergic systems in PAE females may make them less susceptible to the effects of alcohol.

Impacts of COVID-19 in Breast Cancer: From Molecular Mechanism to the Treatment Approach

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has already infected more than 272 million people, resulting in 5.3 million deaths worldwide from COVID-19. Breast tumors are considered the world's most commonly diagnosed cancer. Both breast cancer and COVID-19 share common pathogenic features, represented by inflammatory mediators and the potential of SARS-CoV-2 replication in metastatic cancer cells. This may intensify viral load in patients, thereby triggering severe COVID-19 complications. Thus, cancer patients have a high risk of developing severe COVID-19 with SARS-CoV-2 infection and a higher rate of complications and death than non-cancer patients. The present review discusses common mechanisms between COVID-19 and breast cancer and the particular susceptibility to COVID-19 in breast cancer patients. We describe the effects of chemotherapeutic agents that are used against this cancer, which should be considered from the perspective of susceptibility to SARS-CoV-2 infection and risk of developing severe events. We also present potential drug interactions between chemotherapies that are used to treat breast cancer and drugs that are applied for COVID-19. The drugs that are identified as having the most interactions are doxorubicin and azithromycin. Both drugs can interact with each other and with other drugs, which likely requires additional drug monitoring and changes in drug dosage and timing of administration. Further clinical and observational studies involving breast cancer patients who acquire COVID-19 are needed to define the best therapeutic approach when considering the course of both diseases.

Overlooked sex and gender aspects of emerging infectious disease outbreaks: Lessons learned from COVID-19 to move towards health equity in pandemic response

Sex and gender issues are especially important in emerging infectious diseases (EIDs) but are routinely overlooked despite data and practice. Each of these have an effect either directly, via the effects on vulnerability to infectious diseases, exposures to infectious pathogens, and responses to illness, and indirectly through effects on disease prevention and control programs. The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the viral agent of coronavirus disease 2019 (COVID-19) has underscored the importance of understanding the sex and gender impacts on pandemics. This review takes a broader looks at how sex and gender impact vulnerability, exposure risk, and treatment and response that affect incidence, duration, severity, morbidity, mortality, and disability of EIDs. And although EID epidemic and pandemic plans need to be "pro-women", they need to be broader and include all sex and gender factors. Incorporation of these factors are a priority at the local, national, and global policy levels to fulfil the gaps in scientific research, public health intervention programs and pharmaceutical service strengthening to reduce emerging disease inequities in the population during pandemics and epidemics. A failure to do so creates acceptance of the inequities and infringes on fairness and human rights norms.

Sex difference in circulating soluble form of ACE2 protein in moderate and severe COVID-19 and healthy controls

Introduction

Membrane-bound angiotensin-converting enzyme-2 (ACE2) in epithelial cells is the main receptor for SARS-CoV-2. The extracellular portion of ACE2 may be shedded to plasma in which process ADAM17 (a disintegrin and metalloproteinase 17) is important. Results on the relationship between circulating levels of the soluble form of ACE2 (sACE2) and disease severity are inconclusive. This study investigates if sACE2 concentration correlates with COVID-19 severity, and whether this is affected by sex.

Materials and methods

Soluble form of ACE2 was analyzed in three groups: 104 patients (23 women and 81 men) with severe COVID-19 admitted to an intensive care unit (ICU), patients with moderate COVID-19 who required hospital care (n = 19, 4 women and 15 men), and age and sex matched healthy controls (n = 20, 4 women and 16 men). Blood samples were collected at hospital admission between 18 March 2020, and 3 May 2021, and at follow-up between 27 October 2020, and 19 October 2021. Circulating sACE2 (μg/L) was measured in EDTA plasma with a sensitive enzyme-linked immunosorbent assay. Additionally, CRP, ferritin, and lymphocyte count were analyzed during hospital stay.

Results

In total, 23 patients (22%) died in the ICU. When comparing healthy controls [mean age 58.1 (SD 11.4) years] and patients with moderate COVID-19 [mean age 61.0 (SD 13.2) years] with patients in the ICU [mean age 63.6 (SD 11.6) years], we found that sACE2 concentration decreased (70% reduction) with disease severity in men (p = 0.002) but increased 3.7-fold with severity in women (p = 0.043), suggesting a sex-related difference in how COVID-19 severity is related to sACE2 concentration. Moreover, we identified a relationship between inflammatory biomarkers and sACE2 concentration during the intensive care treatment, such that higher CRP and higher ferritin concentration correlated with lower sACE2 concentration in men.

Conclusion

The decrease in sACE2 concentration, selectively in men, in severe COVID-19 is of pathophysiological interest since men are affected more severely by the disease compared to women. Additionally, the inflammatory biomarkers, CRP and ferritin, correlated inversely with sACE2 concentration, suggesting a role in severe disease. Our findings imply that sACE2 is a possible biomarker of disease severity in a sex-specific manner.

Exposure to a mixture of per-and polyfluoroalkyl substances modulates pulmonary expression of ACE2 and circulating hormones and cytokines

Genetic and environmental factors impact on the interindividual variability of susceptibility to communicable and non-communicable diseases. A class of ubiquitous chemicals, Per- and polyfluoroalkyl substances (PFAS) have been linked in epidemiological studies to immunosuppression and increased susceptibility to viral infections, but possible mechanisms are not well elucidated. To begin to gain insight into the role of PFAS in susceptibility to one such viral infection, Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), male and female C57BL/6 J mice were exposed to control water or a mixture of 5 PFAS (PFOS, PFOA, PFNA, PFHxS, Genx) for 12 weeks and lungs were isolated for examination of expression of SARS-CoV-2-related receptors Angiotensin-Converting Enzyme 2 (ACE2) and others. Secondary analyses included circulating hormones and cytokines which have been shown to directly or indirectly impact on ACE2 expression and severity of viral infections. Changes in mRNA and protein expression were analyzed by RT-qPCR and western blotting and circulating hormones and cytokines were determined by ELISA and MESO QuickPlex. The PFAS mixture decreased Ace2 mRNA 2.5-fold in male mice (p < 0.0001), with no significant change observed in females. In addition, TMPRSS2, ANPEP, ENPEP and DPP4 (other genes implicated in COVID-19 infection) were modulated due to PFAS. Plasma testosterone, but not estrogen were strikingly decreased due to PFAS which corresponded to PFAS-mediated repression of 4 representative pulmonary AR target genes; hemoglobin, beta adult major chain (Hbb-b1), Ferrochelatase (Fech), Collagen Type XIV Alpha 1 Chain (Col14a1), 5'-Aminolevulinate Synthase 2 (Alas2). Finally, PFAS modulated circulating pro and anti-inflammatory mediators including IFN-γ (downregulated 3.0-fold in females; p = 0.0301, 2.1-fold in males; p = 0.0418) and IL-6 (upregulated 5.6-fold in males; p = 0.030, no change in females). In conclusion, our data indicate long term exposure to a PFAS mixture impacts mechanisms related to expression of ACE2 in the lung. This work provides a mechanistic rationale for important future studies of PFAS exposure and subsequent viral infection.

Neurological consequences of COVID-19

In December 2019, cases of pneumonia caused by infection with the previously unknown severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), leading to coronavirus disease 2019 (COVID-19), were identified. Typical manifestations of COVID-19 are fever, cough, fatigue and dyspnoea. Initially, it was thought that the mechanism of action of SARS-CoV-2 was only associated with respiratory tract invasion, but it was later revealed that the infection might involve many other organs and systems, including the central and peripheral nervous systems. Neurological complications associated with SARS-CoV-2 infection include encephalopathy, encephalitis, meningitis, acute disseminated encephalomyelitis (ADEM), ischaemic and haemorrhagic stroke and cerebral venous sinus thrombosis. In cases of peripheral nervous system involvement, smell and taste disorders, myopathy or the signs and symptoms of Guillain‒Barré syndrome are observed. The most common early neurological complications, particularly during the first year of the epidemic, were anosmia and taste disorders, which, according to some studies, occurred in over 80 percent of patients with COVID-19. The proportion of patients with serious neurological manifestations was small compared to the global number of patients, but the numbers of SARS-CoV-2 infections and critical patients increased substantially. The experience from 2 years of the pandemic has shown that approximately 13% of infected patients suffer from severe neurological complications. The relationship between SARS-CoV-2 and the nervous system is not only a cause of neurological complications in previously healthy individuals but also directly and indirectly affects the courses of many nervous system diseases.

Prerequisite for COVID-19 Prediction: A Review on Factors Affecting the Infection Rate

Since the year 2020, coronavirus disease 2019 (COVID-19) has emerged as the dominant topic of discussion in the public and research domains. Intensive research has been carried out on several aspects of COVID-19, including vaccines, its transmission mechanism, detection of COVID-19 infection, and its infection rate and factors. The awareness of the public related to the COVID-19 infection factors enables the public to adhere to the standard operating procedures, while a full elucidation on the correlation of different factors to the infection rate facilitates effective measures to minimize the risk of COVID-19 infection by policy makers and enforcers. Hence, this paper aims to provide a comprehensive and analytical review of different factors affecting the COVID-19 infection rate. Furthermore, this review analyses factors which directly and indirectly affect the COVID-19 infection risk, such as physical distance, ventilation, face masks, meteorological factor, socioeconomic factor, vaccination, host factor, SARS-CoV-2 variants, and the availability of COVID-19 testing. Critical analysis was performed for the different factors by providing quantitative and qualitative studies. Lastly, the challenges of correlating each infection risk factor to the predicted risk of COVID-19 infection are discussed, and recommendations for further research works and interventions are outlined.

Association analysis and expression level of ace polymorphisms with egg-laying trait in Taihang chicken

The number of egg-laying is an important indicator of reproduction performance in poultry breeding. To investigate the relationship between the function of Angiotensin-converting enzyme (ACE) and egg-laying performance of Taihang chicken, the mRNA and protein expression and single nucleotide polymorphism (SNP) of ACE were detected. Analysis of ACE bioinformatics and association analysis of polymorphisms were then performed. The polymorphisms analysis of ACE showed that three SNP loci (g.5066812A>C, g.5080076G>A, and g.5072728A>G) were detected in 800 Taihang chickens with egg-laying records. Association analysis of egg-laying found that ACE g.5066812A>C mutation was significantly associated with the egg-laying performance of Taihang chickens (P < 0.05), and the individuals with the g.5066812A>C mutation showed significantly increasing egg-laying. The mRNA expression was significantly higher in individuals with the AA genotype mutation than those with the AC and CC genotypes (P < 0.01), and the expression of ACE protein levels was consistent with the mRNA expression. Bioinformatics analysis indicated that these mutations affected the secondary and tertiary structure of ACE. This study provides new insights into ACE affecting chicken egg production and some basis for improving the egg production rate of Taihang chickens.

Immune response induced in rodents by anti-CoVid19 plasmid DNA vaccine via pyro-drive jet injector inoculation

There is an urgent need to stop the coronavirus disease 2019 (COVID-19) pandemic through the development of efficient and safe vaccination methods. Over the short term, plasmid DNA vaccines can be developed as they are molecularly stable, thus facilitating easy transport and storage. pVAX1-SARS-CoV2-co was designed for the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) S protein. The antibodies produced led to immunoreactions against the S protein, an anti-receptor-binding-domain, and a neutralizing action of the pVAX1-SARS-CoV2-co, as previously confirmed. To promote the efficacy of the pVAX1-SARS-CoV2-co vaccine a pyro-drive jet injector (PJI) was used. An intradermally adjusted PJI demonstrated that the pVAX1-SARS-CoV2-co vaccine injection caused a high production of anti-S protein antibodies, triggered immunoreactions, and neutralized the actions against SARS-CoV-2. A high-dose pVAX1-SARS-CoV2-co intradermal injection using PJI did not cause any serious disorders in the rat model. A viral challenge confirmed that intradermally immunized mice were potently protected from COVID-19. A pVAX1-SARS-CoV2-co intradermal injection using PJI is a safe and promising vaccination method for overcoming the COVID-19 pandemic.

Atrial cardiomyopathy: from cell to bedside

Atrial cardiomyopathy refers to structural and electrical remodelling of the atria, which can lead to impaired mechanical function. While historical studies have implicated atrial fibrillation as the leading cause of cardioembolic stroke, atrial cardiomyopathy may be an important, underestimated contributor. To date, the relationship between atrial cardiomyopathy, atrial fibrillation, and cardioembolic stroke remains obscure. This review summarizes the pathogenesis of atrial cardiomyopathy, with a special focus on neurohormonal and inflammatory mechanisms, as well as the role of adipose tissue, especially epicardial fat in atrial remodelling. It reviews the current evidence implicating atrial cardiomyopathy as a cause of embolic stroke, with atrial fibrillation as a lagging marker of an increased thrombogenic atrial substrate. Finally, it discusses the potential of antithrombotic therapy in embolic stroke with undetermined source and appraises the available diagnostic techniques for atrial cardiomyopathy, including imaging techniques such as echocardiography, computed tomography, and magnetic resonance imaging as well as electroanatomic mapping, electrocardiogram, biomarkers, and genetic testing. More prospective studies are needed to define the relationship between atrial cardiomyopathy, atrial fibrillation, and embolic stroke and to establish a prompt diagnosis and specific treatment strategies in these patients with atrial cardiomyopathy for the secondary and even primary prevention of embolic stroke.

Angiotensin-converting enzyme 2 and transmembrane protease serine 2 in female and male patients with end-stage kidney disease

BACKGROUND

Individuals with chronic kidney disease are affected by acute respiratory syndrome coronavirus 2 (SARS-CoV-2) due to multiple comorbidities and altered immune system. The first step of the infection process is the binding of SARS-CoV-2 with angiotensin-converting enzyme 2 (ACE2) receptor, followed by its priming by transmembrane protease serine 2 (TMPRSS2). We hypothesized that circulating soluble ACE2 levels, as well as the expressions of ACE2 and TMPRSS2 in the microvasculature, are increased in patients with end-stage kidney disease (ESKD).

METHODS

A total of 210 participants were enrolled, representing 80 ESKD patients and 73 non-CKD controls for soluble ACE2, and 31 ESKD and 26 non-CKD controls for vasculature and fat tissue bioassays. We have assessed ACE2 expression in blood using ELISA and in tissue using immunofluorescence.

RESULTS

Soluble ACE2 levels were higher in ESKD patients compared to controls; however, there is no sex difference observed. In ESKD and controls, soluble ACE2 positively correlated with Interleukin 6 (IL-6) and C-reactive protein (CRP), respectively. Similarly, ACE2 tissue expression in the vasculature was higher in ESKD patients; moreover, this higher ACE2 expression was observed only in male ESKD patients. In addition, TMPRSS2 expression was observed in vessels from males and females but showed no sex difference. The expression of ACE2 receptor was higher in ESKD patients on ACE-inhibitor/angiotensin blocker treatment.

CONCLUSION

ESKD is associated with increased ACE2 levels in the circulation and pronounced in male vasculature; however, further studies are warranted to assess possible sex differences on specific treatment regime(s) for different comorbidities present in ESKD.

Effect of 17β-estradiol on the daily pattern of ACE2, ADAM17, TMPRSS2 and estradiol receptor transcription in the lungs and colon of male rats

Covid-19 progression shows sex-dependent features. It is hypothesized that a better Covid-19 survival rate in females can be attributed to the presence of higher 17β-estradiol (E2) levels in women than in men. Virus SARS-CoV-2 is enabled to enter the cell with the use of angiotensin converting enzyme 2 (ACE2). The expression of several renin-angiotensin system components has been shown to exert a rhythmic pattern, and a role of the circadian system in their regulation has been implicated. Therefore, the aim of the study is to elucidate possible interference between E2 signalling and the circadian system in the regulation of the expression of ACE2 mRNA and functionally related molecules. E2 was administered at a dosage of 40 μg/kg/day for 7 days to male Wistar rats, and sampling of the lungs and colon was performed during a 24-h cycle. The daily pattern of expression of molecules facilitating SARS-CoV-2 entry into the cell, clock genes and E2 receptors was analysed. As a consequence of E2 administration, a rhythm in ACE2 and TMPRSS2 mRNA expression was observed in the lungs but not in the colon. ADAM17 mRNA expression showed a pronounced rhythmic pattern in both tissues that was not influenced by E2 treatment. ESR1 mRNA expression exerted a rhythmic pattern, which was diminished by E2 treatment. The influence of E2 administration on ESR2 and GPER1 mRNA expression was greater in the lungs than in the colon as a significant rhythm in ESR2 and GPER1 mRNA expression appeared only in the lungs after E2 treatment. E2 administration also increased the amplitude of bmal1 expression in the lungs, which implicates altered functioning of peripheral oscillators in response to E2 treatment. The daily pattern of components of the SARS-CoV-2 entrance pathway and their responsiveness to E2 should be considered in the timing of pharmacological therapy for Covid-19.

Systematic Review on Pathophysiological Complications in Severe COVID-19 among the Non-Vaccinated and Vaccinated Population

COVID-19, caused by SARS-CoV-2, is one of the longest viral pandemics in the history of mankind, which have caused millions of deaths globally and induced severe deformities in the survivals. For instance, fibrosis and cavities in the infected lungs of COVID-19 are some of the complications observed in infected patients post COVID-19 recovery. These health abnormalities, including is multiple organ failure-the most striking pathological features of COVID-19-have been linked with diverse distribution of ACE2 receptor. Additionally, several health complications reports were reported after administration of COVID-19 vaccines in healthy individuals, but clinical or molecular pathways causing such complications are not yet studied in detail. Thus, the present systematic review established the comparison of health complication noted in vaccinated and non-vaccinated individuals (COVID-19 infected patients) to identify the association between vaccination and the multiorgan failure based on the data obtained from case studies, research articles, clinical trials/Cohort based studies and review articles published between 2020-2022. This review also includes the biological rationale behind the COVID-19 infection and its subsequent symptoms and effects including multiorgan failure. In addition, multisystem inflammatory syndrome (MIS) has been informed in individuals post vaccination that resulted in multiorgan failure but, no direct correlation of vaccination with MIS has been established. Similarly, hemophagocytic lymphohistiocytosis (HLH) also noted to cause multiorgan failure in some individuals following full vaccination. Furthermore, severe complications were recorded in elderly patients (+40 years of age), indicates that older age individuals are higher risk by COVID-19 and post vaccination, but available literature is not sufficient to comply with any conclusive statements on relationship between vaccination and multiorgan failure.

Angiotensin-(1-7), a protective peptide against vascular aging

Vascular aging is a complex and multifaceted process that provokes profound molecular, structural, and functional changes in the vasculature. Eventually, these profound aging alterations make arteries more prone to vascular disease, including hypertension, atherosclerosis and other arterial complications that impact the organism beyond the cardiovascular system and accelerate frailty. For these reasons, preventing or delaying the hallmarks of vascular aging is nowadays a major health goal, especially in our aged societies. In this context, angiotensin(Ang)-(1-7), a major player of the protective branch of the renin-angiotensin system, has gained relevance over recent years as growing knowledge on its anti-aging properties is being unveiled. Here, we briefly review the main actions of Ang-(1-7) against vascular aging. These include protection against vascular cell senescence, anti-inflammatory and antioxidant effects together with the induction of cytoprotective systems. Ang-(1-7) further ameliorates endothelial dysfunction, a hallmark of vascular aging and disease, attenuates fibrosis and calcification and promotes protective angiogenesis and repair. Although further research is needed to better understand the anti-aging properties of Ang-(1-7) on the vasculature, this heptapeptide arises as a promising pharmacological tool for preventing vascular aging and frailty.

What Should We Do after the COVID-19 Vaccination? Vaccine-Associated Diseases and Precautionary Measures against Adverse Reactions

COVID-19 vaccines have been used to counteract the global COVID-19 pandemic. While these are effective, adverse reactions have been reported, such as injection-site pain, muscle ache, fever, palpitation, and chest discomfort. The release of inflammatory cytokines, such as interleukin (IL)-6 and IL-1β, is a potential mechanism for post-vaccine side-effects. Chest discomfort after the vaccination, including myocarditis and acute coronary syndrome, is a particularly serious adverse reaction. It is important to be familiar with the differential diagnoses of chest discomfort and organ-specific diseases associated with COVID-19 vaccines as the preparation for booster shots and vaccinations among children aged 5–11 years begins. High-intensity exercise, alcohol, tobacco smoking, and baths promote inflammatory cytokines, such as IL-6, which may exacerbate the adverse reactions after vaccination. Japanese data show that deaths during baths are the most common for several days after mRNA vaccination. Additionally, alcohol and tobacco smoking were identified as predictive factors of lower antibody titers after vaccination. In this review, we aimed to provide a few recommendations to prevent vaccine-associated disease.

Clinical Manifestations of COVID-19 Breakthrough Infections: A Systematic Review and Meta-Analysis

To provide a comparative meta‐analysis and systematic review of the risk and clinical outcomes of coronavirus 2019 (COVID‐19) infection between fully vaccinated and unvaccinated groups. Eighteen studies of COVID‐19 infections in fully vaccinated (“breakthrough infections”) and unvaccinated individuals were reviewed from Medline/PubMed, Scopus, Embase, and Web of Science databases. The meta‐analysis examined the summary effects and between‐study heterogeneity regarding differences in the risk of infection, hospitalization, treatments, and mortality between vaccinated and unvaccinated individuals. he overall risk of infection was lower for the fully vaccinated compared to that of the unvaccinated (relative risk [RR] 0.20, 95% confidence interval [CI]: 0.19−0.21), especially for variants other than Delta (Delta: RR 0.29, 95% CI: 0.13−0.65; other variants: RR 0.06, 95% CI: 0.04−0.08). The risk of asymptomatic infection was not statistically significantly different between fully vaccinated and unvaccinated (RR 0.56, 95% CI: 0.27−1.19). There were neither statistically significant differences in risk of hospitalization (RR 1.06, 95% CI: 0.38−2.93), invasive mechanical ventilation (RR 1.65, 95% CI: 0.90−3.06), or mortality (RR 1.19, 95% CI: 0.79−1.78). Conversely, the risk of supplemental oxygen during hospitalization was significantly higher for the unvaccinated (RR 1.40, 95% CI: 1.08−1.82). Unvaccinated people were more vulnerable to COVID‐19 infection than fully vaccinated for all variants. Once infected, there were no statistically significant differences in the risk of hospitalization, invasive mechanical ventilation, or mortality. Still, unvaccinated showed an increased need for oxygen supplementation. Further prospective analysis, including patients’ risk factors, COVID‐19 variants, and the utilized treatment strategies, would be warranted.

The Influence of Sex, Gender, and Age on COVID-19 Data in the Piedmont Region (Northwest Italy): The Virus Prefers Men

Several important sex and gender differences in the clinical manifestation of diseases have been known for a long time but are still underestimated. The infectious Coronavirus 2019 disease pandemic has provided evidence of the importance of a sex and gender-based approach; it mainly affected men with worse symptomatology due to a different immune system, which is stronger in women, and to the Angiotensin-converting enzyme 2 and Transmembrane protease serine 2 roles which are differently expressed among the sexes. Additionally, women are more inclined to maintain social distance and smoke less. Analysis of data on the infectious Coronavirus 2019 disease testing from people admitted to the Amedeo di Savoia Hospital, a regional referral center for infectious diseases, has been applied to the whole of 2020 data (254,640 records). A high percentage of data in the dataset was not suitable due to a lack of information or entering errors. Among the suitable samples, records have been analyzed for positive/negative outcomes, matching records for unique subjects (N = 123,542), to evaluate individual recurrence of testing. Data are presented in age and sex-disaggregated ways. Analyses of the suitable sample also concerned the relation between testing and hospital admission motivation and symptoms. Our analysis indicated that a sex and gender-based approach is mandatory for patients and the National Health System’s sustainability.

SARS-CoV-2 Infection, Sex-Related Differences, and a Possible Personalized Treatment Approach with Valproic Acid: A Review

Sex differences identified in the COVID-19 pandemic are necessary to study. It is essential to investigate the efficacy of the drugs in clinical trials for the treatment of COVID-19, and to analyse the sex-related beneficial and adverse effects. The histone deacetylase inhibitor valproic acid (VPA) is a potential drug that could be adapted to prevent the progression and complications of SARS-CoV-2 infection. VPA has a history of research in the treatment of various viral infections. This article reviews the preclinical data, showing that the pharmacological impact of VPA may apply to COVID-19 pathogenetic mechanisms. VPA inhibits SARS-CoV-2 virus entry, suppresses the pro-inflammatory immune cell and cytokine response to infection, and reduces inflammatory tissue and organ damage by mechanisms that may appear to be sex-related. The antithrombotic, antiplatelet, anti-inflammatory, immunomodulatory, glucose- and testosterone-lowering in blood serum effects of VPA suggest that the drug could be promising for therapy of COVID-19. Sex-related differences in the efficacy of VPA treatment may be significant in developing a personalised treatment strategy for COVID-19.

Sex- and gender-related differences linked to SARS-CoV-2 infection among the participants in the web-based EPICOVID19 survey: the hormonal hypothesis

Objective To investigate sex- and gender-based differences linked to SARS-COV-2 infection and to explore the role of hormonal therapy (HT) in females.

Study design Data from the self-administered, cross-sectional, web-based EPICOVID19 survey of 198,822 adults living in Italy who completed an online questionnaire during the first wave of the epidemic in Italy (April-May 2020) were analyzed.

Main outcomes measures Multivariate binary logistic and multinomial regression models were respectively used to estimate the odds ratios (ORs) with 95% confidence intervals (CIs) for positive nasopharyngeal swab (NPS) test results and severe SARS-CoV-2 infection.

Results The data from 6,873 participants (mean age 47.9 ± 14.1 years, 65.8% females) who had a known result from an NPS test were analyzed. According to the multivariate analysis, females had lower odds of a positive result from the NPS test (aOR 0.75, 95%CI 0.66–0.85) and of having a severe infection (aOR 0.46, 95%CI 0.37–0.57) than did their male counterparts. These differences were greater with decreasing age in both sexes. In addition, females aged ≥60 years receiving HT (N = 2,153, 47.6%) had a 46% lower probability of having a positive NPS test (aOR 0.54, 95%CI 0.36–0.80) than their same-aged peers who had never used HT; there were no differences in the younger age groups with respect to HT status.

Conclusion Female sex was associated with an age-dependent lower risk of having a severe SARS-CoV-2 infection than their male counterparts. Age seemed to modify the relationship between HT status and infection: while the two were not related among younger participants, it was negative in the older ones. Future prospective studies are needed to elucidate the potential protective role sex hormones may play.

Trial registration ClinicalTrials.gov NCT04471701.

Can Epigenetics Help Solve the Puzzle Between Concomitant Cardiovascular Injury and Severity of Coronavirus Disease 2019?

ABSTRACT

The ongoing coronavirus disease 2019 (COVID-19) pandemic caused by SARS-CoV-2 has significant implications in patients with concomitant cardiovascular disease (CVD) because they are the population at the greatest risk of death. The treatment of such patients and complications may represent a new challenge for the fields of cardiology and pharmacology. Thus, understanding the involvement of this viral infection in CVD might help to reduce the aggressiveness of SARS-CoV-2 in causing multiorgan infection and damage. SARS-CoV-2 disturbs the host epigenome and several epigenetic processes involved in the pathophysiology of COVID-19 that can directly affect the function and structure of the cardiovascular system (CVS). Hence, it would be relevant to identify epigenetic alterations that directly impact CVS physiology after SARS-CoV-2 infection. This could contribute to the view of this virus-induced CVS injury and direct forthcoming tackles for COVID-19 treatment to reduce mortality in patients with CVD. Targeting epigenetic marks could offer strong evidence for the development of novel antiviral therapies, especially in the context of COVID-19-related CVS damage. In this review, we address some of the main signaling pathways that are currently known as being involved in COVID-19 pathophysiology and the importance of this glint on epigenetics and some of its modifiers (epidrugs) to control the unregulated epitope activity in the context of SARS-CoV-2 infection, COVID-19, and underlying CVD.

Endothelial Dysfunction in COVID-19: A Unifying Mechanism and a Potential Therapeutic Target

The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) generated a worldwide emergency, until the declaration of the pandemic in March 2020. SARS-CoV-2 could be responsible for coronavirus disease 2019 (COVID-19), which goes from a flu-like illness to a potentially fatal condition that needs intensive care. Furthermore, the persistence of functional disability and long-term cardiovascular sequelae in COVID-19 survivors suggests that convalescent patients may suffer from post-acute COVID-19 syndrome, requiring long-term care and personalized rehabilitation. However, the pathophysiology of acute and post-acute manifestations of COVID-19 is still under study, as a better comprehension of these mechanisms would ensure more effective personalized therapies. To date, mounting evidence suggests a crucial endothelial contribution to the clinical manifestations of COVID-19, as endothelial cells appear to be a direct or indirect preferential target of the virus. Thus, the dysregulation of many of the homeostatic pathways of the endothelium has emerged as a hallmark of severity in COVID-19. The aim of this review is to summarize the pathophysiology of endothelial dysfunction in COVID-19, with a focus on personalized pharmacological and rehabilitation strategies targeting endothelial dysfunction as an attractive therapeutic option in this clinical setting.

Adverse events and Breakthrough infections associated with COVID-19 vaccination in the Indian population

Vaccines against COVID‐19 provide immunity to deter severe morbidities associated with the infection. However, it does not prevent infection altogether in all exposed individuals. Furthermore, emerging variants of SARS‐CoV‐2 impose a threat concerning the competency of the vaccines in combating the infection. This study aims to determine the variability in adverse events and the extent of breakthrough infections in the Indian population. A retrospective study was conducted using a pre‐validated questionnaire encompassing social, demographic, general health, the status of SARS‐CoV‐2 infection, vaccination, associated adverse events, and breakthrough infections in the Indian population. Informed consent and ethical approval were obtained as per Indian Council of Medical Research (ICMR) guidelines. Participants, who provided the complete information, were Indian citizens, above 18 years, and if vaccinated, administered with either Covishield or Covaxin, were considered for the study. Data have been compiled in Microsoft Excel and analyzed for statistical differences using STATA 11. The responses from 2051 individuals fulfilling the inclusion criteria were analyzed. Among 2051, 1119 respondents were vaccinated and 932 respondents were non‐vaccinated. Among 1119 vaccinated respondents, 7 were excluded because of missing data. Therefore, out of 1112 vaccinated, 413 experienced adverse events with a major fraction of younger individuals, age 18–40 years, getting affected (74.82%; 309/413). Furthermore, considerably more females than males encountered adverse consequences to vaccination (p < 0.05). Among vaccinated participants, breakthrough infections were observed in 7.91% (88/1112; 57.96% males and 42.04% females) with the older age group, 61 years and above (odds ratio, 3.25 [1.32–8.03]; p = 0.011), and males were found to be at higher risk. Further research is needed to find the age and sex‐related factors in determining vaccine effectiveness and adverse events.

Significant higher adverse events following COVID‐19 vaccination in females in comparison to males.

Breakthrough infections among Indian population was found to be 7.91%.

Older people and males were found to be at high risk for getting breakthrough infections.

Molecular and Physiological Aspects of SARS-CoV-2 Infection in Women and Pregnancy

Whilst scientific knowledge about SARS-CoV-2 and COVID-19 is rapidly increasing, much of the effects on pregnant women is still unknown. To accommodate pregnancy, the human endometrium must undergo a physiological transformation called decidualization. These changes encompass the remodeling of endometrial immune cells leading to immunotolerance of the semi-allogenic conceptus as well as defense against pathogens. The angiotensin converting enzyme 2 (ACE2) plays an important regulatory role in the renin-angiotensin-system (RAS) and has been shown to be protective against comorbidities known to worsen COVID-19 outcomes. Furthermore, ACE2 is also crucial for decidualization and thus for early gestation. An astounding gender difference has been found in COVID-19 with male patients presenting with more severe cases and higher mortality rates. This could be attributed to differences in sex chromosomes, hormone levels and behavior patterns. Despite profound changes in the female body during pregnancy, expectant mothers do not face worse outcomes compared with non-pregnant women. Whereas mother-to-child transmission through respiratory droplets during labor or in the postnatal period is known, another question of in utero transmission remains unanswered. Evidence of placental SARS-CoV-2 infection and expression of viral entry receptors at the maternal-fetal interface suggests the possibility of in utero transmission. SARS-CoV-2 can cause further harm through placental damage, maternal systemic inflammation, and hindered access to health care during the pandemic. More research on the effects of COVID-19 during early pregnancy as well as vaccination and treatment options for gravid patients is urgently needed.

An Updated Review on the Role of Single Nucleotide Polymorphisms in COVID-19 Disease Severity: A Global Aspect

Abstract:

Coronavirus disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and recently has become a serious global pandemic. Age, gender, and comorbidities are known to be common risk factors for severe COVID-19 but are not enough to fully explain the magnitude of their effect on the risk of severity of the disease. Single nucleotide polymorphisms (SNPs) in several genes have been reported as a genetic factor contributing to COVID-19 severity. This comprehensive review focuses on the association between SNPs in four important genes and COVID-19 severity in a global aspect. We discuss a total of 39 SNPs in this review: five SNPs in the ABO gene, nine SNPs in the angiotensin-converting enzyme 2 (ACE2) gene, 19 SNPs in the transmembrane protease serine 2 (TMPRSS2) gene, and six SNPs in the toll-like receptor 7 (TLR7) gene. These SNPs data could assist in monitoring an individual's risk of severe COVID-19 disease, and therefore personalized management and pharmaceutical treatment could be planned in COVID-19 patients.

TMPRSS2 Expression and Activity Modulation by Sex-Related Hormones in Lung Calu-3 Cells: Impact on Gender-Specific SARS-CoV-2 Infection

Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Although males and females are at equivalent risk of infection, males are more prone to develop a higher severity disease, regardless of age. The factors that mediate susceptibility to SARS-CoV-2 and transmission are still under investigation. A potential role has been attributed to differences in the immune systems response to viral antigens between males and females as well as to different regulatory actions played by sex-related hormones on the two crucial molecular effectors for SARS-CoV-2 infection, TMPRSS2 and ACE2. While few and controversial data about TMPRSS2 transcript regulation in lung cells are emerging, no data on protein expression and activity of TMPRSS2 have been reported. Aim of the present study was to search for possible modulatory actions played by sex-related hormones on TMPRSS2 and ACE2 expression in Calu-3 cells, to test the effects of sex-steroids on the expression of the 32kDa C-term fragment derived from autocatalitic cleavage of TMPRSS2 and its impact on priming of transiently transfected spike protein. Cells were stimulated with different concentrations of methyltrienolone (R1881) or estradiol for 30 h. No difference in mRNA and protein expression levels of full length TMPRSS2 was observed. However, the 32 kDa cleaved serine protease domain was increased after 100 nM R1881 (+2.36 ± 1.13 fold-increase vs control untreated cells, p < 0.05) and 10 nM estradiol (+1.90 ± 0.64, fold-increase vs control untreated cells, p < 0.05) treatment. Both R1881 and estradiol significantly increased the activating proteolytic cleavage of SARS-CoV-2 Spike (S) transfected in Calu-3 cells (+1.76 ± 0.18 and +1.99±,0.76 increase in S cleavage products at R1881 100nM and 10 nM estradiol treatment, respectively, p < 0.001 and p < 0.05 vs control untreated cells, respectively). Finally, no significant differences in ACE2 expression were observed between hormones-stimulated cells and untreated control cells. Altogether, these data suggest that both male and female sex-related hormones are able to induce a proteolityc activation of TMPRSS2, thus promoting viral infection, in agreement with the observation that males and females are equally infected by SARS-CoV-2.

Roles of steroid receptors in the lung and COVID-19

COVID-19 symptoms and mortality are largely due to its devastating effects in the lungs. The disease is caused by the SARS (Severe Acute Respiratory Syndrome)-CoV-2 coronavirus, which requires host cell proteins such as ACE2 (angiotensin-converting enzyme 2) and TMPRSS2 (transmembrane serine protease 2) for infection of lung epithelia. The expression and function of the steroid hormone receptor family is important in many aspects that impact on COVID-19 effects in the lung - notably lung development and function, the immune system, and expression of TMPRSS2 and ACE2. This review provides a brief summary of current knowledge on the roles of the steroid hormone receptors [androgen receptor (AR), glucocorticoid receptor (GR), progesterone receptor (PR), mineralocorticoid receptor (MR) and oestrogen receptor (ER)] in the lung, their effects on host cell proteins that facilitate SARS-CoV-2 uptake, and provides a snapshot of current clinical trials investigating the use of steroid receptor (SR) ligands to treat COVID-19.

The Identikit of Patient at Risk for Severe COVID-19 and Death: The Dysregulation of Renin-Angiotensin System as the Common Theme

Since the first months of the coronavirus disease 2019 (COVID-19) pandemic, several specific physiologic traits, such as male sex and older age, or health conditions, such as overweight/obesity, arterial hypertension, metabolic syndrome, and type 2 diabetes mellitus, have been found to be highly prevalent and associated with increased risk of adverse outcomes in hospitalized patients. All these cardiovascular morbidities are widespread in the population and often coexist, thus identifying a common patient phenotype, characterized by a hyper-activation of the “classic” renin-angiotensin system (RAS) and mediated by the binding of angiotensin II (Ang II) to the type 1-receptor. At the same time, the RAS imbalance was proved to be crucial in the genesis of lung injury after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, where angiotensin-converting-enzyme-2 (ACE2) is not only the receptor for SARS-CoV-2, but its down-regulation through internalization and shedding, caused by the virus binding, leads to a further dysregulation of RAS by reducing angiotensin 1-7 (Ang 1-7) production. This focused narrative review will discuss the main available evidence on the role played by cardiovascular and metabolic conditions in severe COVID-19, providing a possible pathophysiological link based on the disequilibrium between the two opposite arms of RAS.

Sex-related susceptibility in coronavirus disease 2019 (COVID-19): Proposed mechanisms

The importance of sex differences is increasingly acknowledged in the incidence and treatment of disease. Accumulating clinical evidence demonstrates that sex differences are noticeable in COVID-19, and the prevalence, severity, and mortality rate of COVID-19 are higher among males than females. Sex-related genetic and hormonal factors and immunological responses may underlie the sex bias in COVID-19 patients. Angiotensin-converting enzyme 2 (ACE2) and transmembrane protease/serine subfamily member 2 (TMPRSS2) are essential proteins involved in the cell entry of SARS-CoV-2. Since ACE2 is encoded on the X-chromosome, a double copy of ACE2 in females may compensate for virus-mediated downregulation of ACE2, and thus ACE2-mediated cellular protection is greater in females. The X chromosome also contains the largest immune-related genes leading females to develop more robust immune responses than males. Toll-like receptor-7 (TLR-7), one of the key players in innate immunity, is linked to sex differences in autoimmunity and vaccine efficacy, and its expression is greater in females. Sex steroids also affect immune cell function. Estrogen contributes to higher CD4⁺ and CD8⁺ T cell activation levels, and females have more B cells than males. Sex differences not only affect the severity and progression of the disease, but also alter the efficacy of pharmacological treatment and adverse events related to the drugs/vaccines used against COVID-19. Administration of different drugs/vaccines in different doses or intervals may be useful to eliminate sex differences in efficacy and side/adverse effects. It should be noted that studies should include sex-specific analyses to develop further sex-specific treatments for COVID-19.

The gut microbiome as a biomarker of differential susceptibility to SARS-CoV-2

Coronavirus disease 2019 (COVID-19) continues to exact a devastating global toll. Ascertaining the factors underlying differential susceptibility and prognosis following viral exposure is critical to improving public health responses. We propose that gut microbes may contribute to variation in COVID-19 outcomes. We synthesise evidence for gut microbial contributions to immunity and inflammation, and associations with demographic factors affecting disease severity. We suggest mechanisms potentially underlying microbially mediated differential susceptibility to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). These include gut microbiome-mediated priming of host inflammatory responses and regulation of endocrine signalling, with consequences for the cellular features exploited by SARS-CoV-2 virions. We argue that considering gut microbiome-mediated mechanisms may offer a lens for appreciating differential susceptibility to SARS-CoV-2, potentially contributing to clinical and epidemiological approaches to understanding and managing COVID-19.

The Renin-Angiotensin-Aldosterone System in Postmenopausal Women: The Promise of Hormone Therapy

Estradiol (E2) plays an underrecognized role in modulating body-wide systems, including important interactions with the renin-angiotensin-aldosterone system (RAAS). The RAAS is an immunomodulating system that is critical for maintaining homeostasis across multiple organ systems. The diverse interactions between E2 and the RAAS help maintain cardiometabolic homeostasis, including successful physiologic responses to trauma and infectious pathogens. Estradiol deficiency (ie, menopause) results in impaired responses and increased susceptibility to infectious pathogens. Both immune and cardiometabolic function decline with reduced E2 production, in part because the RAAS becomes dysregulated by E2 deficiency, leaving RAAS predominantly in its proinflammatory state and predisposing to systemic low-grade inflammation. Estradiol deficiency and RAAS dysregulation contribute to impaired immune responses and increased incidence of cardiac hypertrophy, hypertension, atherosclerotic cardiovascular disease, arrhythmias, and heart failure. The RAAS consists of dual, counterbalancing pathways-proinflammatory and anti-inflammatory. Estradiol is a signaling agent that plays a major role in determining which RAAS pathway predominates. The proinflammatory pathway is activated early in response to infection or trauma, followed by up-regulation of the anti-inflammatory pathway, to resolve inflammation and to restore homeostasis. Estradiol influences activation of the "switch" to restore the anti-inflammatory state. The dysregulated RAAS is a primary target of current cardiovascular therapeutics focused on blocking portions of its proinflammatory pathway. However, RAAS-modifying pharmaceuticals often provide imperfect solutions to these physiologic disruptions and underscore the need for improved approaches to menopausal medicine. Estradiol therapy and optimal lifestyle practices combined with RAAS-modifying pharmaceuticals may be an ideal strategy to optimize postmenopausal health.

Sexual dimorphism in cardiac remodeling: the molecular mechanisms ruled by sex hormones in the heart

Heart failure (HF) is growing in prevalence, due to an increase in aging and comorbidities. Heart failure with reduced ejection fraction (HFrEF) is more common in men, whereas heart failure with preserved ejection fraction (HFpEF) has a higher prevalence in women. However, the reasons for these epidemiological trends are not clear yet. Since HFpEF affects mostly postmenopausal women, sex hormones should play a pivotal role in HFpEF development. Furthermore, for HFpEF, contrary to HFrEF, effective therapeutic approaches are missing. Interestingly, studies evidenced that some therapies can have better results in women than in HFpEF men, emphasizing the necessity of understanding these observations at a molecular level. Thus, herein, we review the molecular mechanisms of estrogen and androgen actions in the heart in physiological conditions and explain how its dysregulation can lead to disease development. This clarification is essential in the road for an effective personalized management of HF, particularly HFpEF, towards the development of sex-specific therapeutic approaches.

Predicting respiratory failure in patients infected by SARS-CoV-2 by admission sex-specific biomarkers

BACKGROUND

Several biomarkers have been identified to predict the outcome of COVID-19 severity, but few data are available regarding sex differences in their predictive role. Aim of this study was to identify sex-specific biomarkers of severity and progression of acute respiratory distress syndrome (ARDS) in COVID-19.

METHODS

Plasma levels of sex hormones (testosterone and 17β-estradiol), sex-hormone dependent circulating molecules (ACE2 and Angiotensin1-7) and other known biomarkers for COVID-19 severity were measured in male and female COVID-19 patients at admission to hospital. The association of plasma biomarker levels with ARDS severity at admission and with the occurrence of respiratory deterioration during hospitalization was analysed in aggregated and sex disaggregated form.

RESULTS

Our data show that some biomarkers could be predictive both for males and female patients and others only for one sex. Angiotensin1-7 plasma levels and neutrophil count predicted the outcome of ARDS only in females, whereas testosterone plasma levels and lymphocytes counts only in males.

CONCLUSIONS

Sex is a biological variable affecting the choice of the correct biomarker that might predict worsening of COVID-19 to severe respiratory failure. The definition of sex specific biomarkers can be useful to alert patients to be safely discharged versus those who need respiratory monitoring.

COVID-19 Vaccination-Associated Myocarditis in Adolescents

OBJECTIVES

In this study, we aimed to characterize the clinical presentation, short-term prognosis, and myocardial tissue changes as noted on cardiovascular magnetic resonance (CMR) or cardiac MRI in pediatric patients with coronavirus disease 2019 vaccination-associated myocarditis (C-VAM).

METHODS

In this retrospective multicenter study across 16 US hospitals, patients <21 years of age with a diagnosis of C-VAM were included and compared with a cohort with multisystem inflammatory syndrome in children. Younger children with C-VAM were compared with older adolescents.

RESULTS

Sixty-three patients with a mean age of 15.6 years were included; 92% were male. All had received a messenger RNA vaccine and, except for one, presented after the second dose. Four patients had significant dysrhythmia; 14% had mild left ventricular dysfunction on echocardiography, which resolved on discharge; 88% met the diagnostic CMR Lake Louise criteria for myocarditis. Myocardial injury as evidenced by late gadolinium enhancement on CMR was more prevalent in comparison with multisystem inflammatory syndrome in children. None of the patients required inotropic, mechanical, or circulatory support. There were no deaths. Follow-up data obtained in 86% of patients at a mean of 35 days revealed resolution of symptoms, arrhythmias, and ventricular dysfunction.

CONCLUSIONS

Clinical characteristics and early outcomes are similar between the different pediatric age groups in C-VAM. The hospital course is mild, with quick clinical recovery and excellent short-term outcomes. Myocardial injury and edema are noted on CMR. Close follow-up and further studies are needed to understand the long-term implications and mechanism of these myocardial tissue changes.

Epidemiological Analysis of SARS-CoV-2 Transmission Dynamics in the State of Odisha, India: A Yearlong Exploratory Data Analysis

COVID-19 remains a matter of global public health concern. Previous research suggested the association between local environmental factors and viral transmission. We present a multivariate observational analysis of SARS-CoV-2 transmission in the state of Odisha, India, hinting at a seasonal activity. We aim to investigate the demographic characteristics of COVID-19 in the Indian state of Odisha for two specific timelines in 2020 and 2021. For a comparative outlook, we chose similar datasets from the state of New York, USA. Further, we present a critical analysis pertaining to the effects of environmental factors and the emergence of variants on SARS-CoV-2 transmission and persistence. We assessed the datasets for confirmed cases, death, age, and gender for 29 February 2020 to 31 May 2020, and 1 March 2021 to 31 May 2021. We determined the case fatalities, crude death rates, sex ratio, and incidence rates for both states along with monthly average temperature analysis. A yearlong epi-curve analysis was conducted to depict the coronavirus infection spread pattern in the respective states. The Indian state of Odisha reported a massive 436,455 confirmed cases and 875 deaths during the 2021 timeline as compared to a mere 2223 cases and 7 deaths during the 2020 timeline. We further discuss the demographic and temperature association of SARS-CoV-2 transmission during early 2020 and additionally comment on the variant-associated massive rise in cases during 2021. Along with the rapid rise of variants, the high population density and population behavior seem to be leading causes for the 2021 pandemic, whereas factors such as age group, gender, and average local temperature were prominent during the 2020 spread. A seasonal occurrence of SARS-CoV-2 transmission is also observed from the yearlong epidemiological plot. The recent second wave of COVID-19 is a lesson that emphasizes the significance of continuous epidemiological surveillance to predict the relative risk of viral transmission for a specific region.

Gender Characteristics of the Novel Coronavirus Infection (COVID-19) in Middle-Aged Adults

The aim of the study is to assess the gender-related specifics of the COVID-19 course in patients under 55 years of age.

Atrial Cardiomyopathy: Pathophysiology and Clinical Consequences

Around the world there are 33.5 million patients suffering from atrial fibrillation (AF) with an annual increase of 5 million cases. Most AF patients have an established form of an atrial cardiomyopathy. The concept of atrial cardiomyopathy was introduced in 2016. Thus, therapy of underlying diseases and atrial tissue changes appear as a cornerstone of AF therapy. Furthermore, therapy or prevention of atrial endocardial changes has the potential to reduce atrial thrombogenesis and thereby cerebral stroke. The present manuscript will summarize the underlying pathophysiology and remodeling processes observed in the development of an atrial cardiomyopathy, thrombogenesis, and atrial fibrillation. In particular, the impact of oxidative stress, inflammation, diabetes, and obesity will be addressed.

Testosterone in COVID-19: An Adversary Bane or Comrade Boon

COVID-19 is a pandemic disease caused by severe acute respiratory coronavirus 2 (SARS-CoV-2), which leads to pulmonary manifestations like acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). In addition, COVID-19 may cause extra-pulmonary manifestation such as testicular injury. Both high and low levels of testosterone could affect the severity of COVID-19. Herein, there is substantial controversy regarding the potential role of testosterone in SARS-CoV-2 infection and COVID-19 severity. Therefore, the present study aimed to review and elucidate the assorted view of preponderance regarding the beneficial and harmful effects of testosterone in COVID-19. A related literature search in PubMed, Scopus, Web of Science, Google Scholar, and Science Direct was done. All published articles related to the role of testosterone and COVID-19 were included in this mini-review. The beneficial effects of testosterone in COVID-19 are through inhibition of pro-inflammatory cytokines, augmentation of anti-inflammatory cytokines, modulation of the immune response, attenuation of oxidative stress, and endothelial dysfunction. However, its harmful effects in COVID-19 are due to augmentation of transmembrane protease serine 2 (TMPRSS2), which is essential for cleaving and activating SARS-CoV-2 spike protein during acute SARS-CoV-2 infection. Most published studies illustrated that low testosterone levels are linked to COVID-19 severity. A low testosterone level in COVID-19 is mainly due to testicular injury, the primary source of testosterone.

SARS-CoV-2 Spike Protein Regulation of Angiotensin Converting Enzyme 2 and Tissue Renin-Angiotensin Systems: Influence of Biologic Sex

Angiotensin converting enzyme 2 (ACE2) is an enzyme that limits activity of the renin-angiotensin system (RAS) and also serves as a receptor for the SARS-CoV-2 Spike (S) protein. Binding of S protein to ACE2 causes internalization which activates local RAS. ACE2 is on the X chromosome and its expression is regulated by sex hormones. In this study, we defined ACE2 mRNA abundance and examined effects of S protein on ACE2 activity and/or angiotensin II (AngII) levels in pivotal tissues (lung, adipose) from male and female mice. In lung, ACE2 mRNA abundance was reduced following gonadectomy (GDX) of male and female mice and was higher in XX than XY mice of the Four Core Genotypes (FCG). Reductions in lung ACE2 mRNA abundance by GDX occurred in XX, but not XY FCG female mice. Lung mRNA abundance of ADAM17 and TMPRSS2, enzymes that shed cell surface ACE2 and facilitate viral cell entry, was reduced by GDX in male but not female mice. For comparison, adipose ACE2 mRNA abundance was higher in female than male mice and higher in XX than XY FCG mice. Adipose ADAM17 mRNA abundance was increased by GDX of male and female mice. S protein reduced ACE2 activity in alveolar type II epithelial cells and 3T3-L1 adipocytes. Administration of S protein to male and female mice increased lung AngII levels and decreased adipose ACE2 activity in male but not female mice. These results demonstrate that sex differences in ACE2 expression levels may impact local RAS following S protein exposures.

Vitamin D and COVID-19: Role of ACE2, age, gender, and ethnicity

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus, disproportionally targets older people, particularly men, ethnic minorities, and individuals with underlying diseases such as compromised immune system, cardiovascular disease, and diabetes. The discrepancy in COVID-19 incidence and severity is multifaceted and likely involves biological, social, as well as nutritional status. Vitamin D deficiency, notably common in Black and Brown people and elderly, is associated with an increased susceptibility to many of the diseases comorbid with COVID-19. Vitamin D deficiency can cause over-activation of the pulmonary renin-angiotensin system (RAS) leading to the respiratory syndrome. RAS is regulated in part at least by angiotensin-converting enzyme 2 (ACE2), which also acts as a primary receptor for SARS-CoV-2 entry into the cells. Hence, vitamin D deficiency can exacerbate COVID-19, via its effects on ACE2. In this review we focus on influence of age, gender, and ethnicity on vitamin D-ACE2 interaction and susceptibility to COVID-19.

Sex-tailored pharmacology and COVID-19: Next steps towards appropriateness and health equity

Making gender bias visible allows to fill the gaps in knowledge and understand health records and risks of women and men. The coronavirus disease 2019 (COVID-19) pandemic has shown a clear gender difference in health outcomes. The more severe symptoms and higher mortality in men as compared to women are likely due to sex and age differences in immune responses. Age-associated decline in sex steroid hormone levels may mediate proinflammatory reactions in older adults, thereby increasing their risk of adverse outcomes, whereas sex hormones and/or sex hormone receptor modulators may attenuate the inflammatory response and provide benefit to COVID-19 patients. While multiple pharmacological options including anticoagulants, glucocorticoids, antivirals, anti-inflammatory agents and traditional Chinese medicine preparations have been tested to treat COVID-19 patients with varied levels of evidence in terms of efficacy and safety, information on sex-targeted treatment strategies is currently limited. Women may have more benefit from COVID-19 vaccines than men, despite the occurrence of more frequent adverse effects, and long-term safety data with newly developed vectors are eagerly awaited. The prevalent inclusion of men in randomized clinical trials (RCTs) with subsequent extrapolation of results to women needs to be addressed, as reinforcing sex-neutral claims into COVID-19 research may insidiously lead to increased inequities in health care. The huge worldwide effort with over 3000 ongoing RCTs of pharmacological agents should focus on improving knowledge on sex, gender and age as pillars of individual variation in drug responses and enforce appropriateness.

Immunity, Sex Hormones, and Environmental Factors as Determinants of COVID-19 Disparity in Women

The current coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome virus 2 (SARS-CoV-2), has resulted in a major global pandemic, causing extreme morbidity and mortality. Few studies appear to suggest a significant impact of gender in morbidity and mortality, where men are reported at a higher risk than women. The infectivity, transmissibility, and varying degree of disease manifestation (mild, modest, and severe) in population studies reinforce the importance of a number of genetic and epigenetic factors, in the context of immune response and gender. The present review dwells on several contributing factors such as a stronger innate immune response, estrogen, angiotensin-converting enzyme 2 gene, and microbiota, which impart greater resistance to the SARS-CoV-2 infection and disease progression in women. In addition, the underlying importance of associated microbiota and certain environmental factors in gender-based disparity pertaining to the mortality and morbidity due to COVID-19 in women has also been addressed.