Tag: covid pathophysiology

Quantitative Proteomics of COVID-19 Recovered Patients Identifies Long-Term Changes in Sperm Proteins Leading to Cellular Stress in Spermatozoa

Abstract:

Following an initial recovery, COVID-19 survivors struggle with a spectrum of persistent medical complications, including fatigue, breathlessness, weight loss, hair loss, and attention deficits. Additionally, there is growing evidence of adverse effects of COVID-19 on the male reproductive system. This investigation seeks to understand the long-term ramifications on male fertility by examining hormonal profiles, semen parameters, and sperm proteome of recovered COVID-19 patients compared to controls.

The serum hormone profiles between the two groups showed minimal variations except for prolactin, cortisol, and testosterone levels. Testosterone levels were slightly lower, while prolactin and cortisol were elevated in COVID-19 cases compared to controls.

Though semen parameters exhibited no significant disparities between the COVID-19 and control groups, quantitative proteomics analysis revealed changes in sperm proteins. It identified 190 differentially expressed proteins, of which 161 were upregulated and 29 downregulated in COVID-19 cases.

Western blotting analysis validated the differential expression of serpin B4 and calpain 2. Bioinformatics analysis signifies cellular stress in the spermatozoa of COVID-19 recovered patients and thus, SOD and MDA levels in semen were measured. MDA levels were found to be significantly elevated, indicating lipid peroxidation in COVID-19 samples.

While the effects of COVID-19 on semen parameters may exhibit a potential for reversal within a short duration, the alterations it inflicts on sperm proteome are persisting consequences on male fertility. This study paves the path for further research and emphasizes the significance of comprehending the complex molecular processes underlying the long-term consequences of COVID-19 on male reproductive health.

Source: Chopra P, Tomar AK, Thapliyal A, Ranjan P, Datta SK, Yadav S. Quantitative Proteomics of COVID-19 Recovered Patients Identifies Long-Term Changes in Sperm Proteins Leading to Cellular Stress in Spermatozoa. Reprod Sci. 2024 Apr 24. doi: 10.1007/s43032-024-01560-5. Epub ahead of print. PMID: 38658489. https://pubmed.ncbi.nlm.nih.gov/38658489/

Long COVID: A Molecular, Cellular and Histopathology Overview

Abstract:

Long COVID has been studied as different sequelae that some individuals can develop after the acute phase of the disease. Persistent symptoms such as dry cough, fatigue, and dyspnea can remain after six months of COVID-19 cure. Others such as lung fibrosis, kidney injury, and thrombotic risk also are observed. Here, a deep review of each human organ and system infected by the virus was performed aiming to show how molecules expression and cell signaling can induce the organism cure or injuries and, subsequently sequelae. The review also suggests the importance of public health surveillance for these cases including a more comprehensive analysis of molecular biology tools that can clarify and assist in the prognosis, treatment, and preventive methods for potentially more serious disorders in post-COVID-19 patients.

Source: da Silva Barros, B. , de Oliveira Cruz, L. , de Sousa, G. , Souza-Silva, G. , de Lima, M. , Oliveira, E. , Silva, A. , Macêdo, L. , Leal, L. , Marcos, B. , Elsztein, C. , Invenção, M. , de Freitas, A. and Moutinho-Melo, C. (2023) Long COVID: A Molecular, Cellular and Histopathology Overview. Journal of Biosciences and Medicines, 11, 90-113. doi: 10.4236/jbm.2023.119009. https://www.scirp.org/journal/paperinformation.aspx?paperid=127523 (Full text)

Increased red blood cell deformation in children and adolescents after SARS-CoV-2 infection

Abstract:

Severe coronavirus disease 2019 (COVID-19) is associated with hyperinflammation, hypercoagulability and hypoxia. Red blood cells (RBCs) play a key role in microcirculation and hypoxemia and are therefore of special interest in COVID-19 pathophysiology. While this novel disease has claimed the lives of many older patients, it often goes unnoticed or with mild symptoms in children.

This study aimed to investigate morphological and mechanical characteristics of RBCs after SARS-CoV-2 infection in children and adolescents by real-time deformability-cytometry (RT-DC), to investigate the relationship between alterations of RBCs and clinical course of COVID-19. Full blood of 121 students from secondary schools in Saxony, Germany, was analyzed. SARS-CoV-2-serostatus was acquired at the same time.

Median RBC deformation was significantly increased in SARS-CoV-2-seropositive compared to seronegative children and adolescents, but no difference could be detected when the infection dated back more than 6 months. Median RBC area was the same in seropositive and seronegative adolescents. ‘

Our findings of increased median RBC deformation in SARS-CoV-2 seropositive children and adolescents until 6 months post COVID-19 could potentially serve as a progression parameter in the clinical course of the disease with an increased RBC deformation pointing towards a mild course of COVID-19.

Source: Eder J, Schumm L, Armann JP, Puhan MA, Beuschlein F, Kirschbaum C, Berner R, Toepfner N. Increased red blood cell deformation in children and adolescents after SARS-CoV-2 infection. Sci Rep. 2023 Jun 17;13(1):9823. doi: 10.1038/s41598-023-35692-6. PMID: 37330522. https://www.nature.com/articles/s41598-023-35692-6 (Full text)

Neurovascular injury with complement activation and inflammation in COVID-19

Abstract:

The underlying mechanisms by which severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) leads to acute and long-term neurological manifestations remains obscure. We aimed to characterize the neuropathological changes in patients with coronavirus disease 2019 and determine the underlying pathophysiological mechanisms. In this autopsy study of the brain, we characterized the vascular pathology, the neuroinflammatory changes and cellular and humoral immune responses by immunohistochemistry.

All patients died during the first wave of the pandemic from March to July 2020. All patients were adults who died after a short duration of the infection, some had died suddenly with minimal respiratory involvement. Infection with SARS-CoV-2 was confirmed on ante-mortem or post-mortem testing. Descriptive analysis of the pathological changes and quantitative analyses of the infiltrates and vascular changes were performed.

All patients had multifocal vascular damage as determined by leakage of serum proteins into the brain parenchyma. This was accompanied by widespread endothelial cell activation. Platelet aggregates and microthrombi were found adherent to the endothelial cells along vascular lumina. Immune complexes with activation of the classical complement pathway were found on the endothelial cells and platelets. Perivascular infiltrates consisted of predominantly macrophages and some CD8+ T cells. Only rare CD4+ T cells and CD20+ B cells were present. Astrogliosis was also prominent in the perivascular regions. Microglial nodules were predominant in the hindbrain, which were associated with focal neuronal loss and neuronophagia.

Antibody-mediated cytotoxicity directed against the endothelial cells is the most likely initiating event that leads to vascular leakage, platelet aggregation, neuroinflammation and neuronal injury. Therapeutic modalities directed against immune complexes should be considered.

Source: Lee MH, Perl DP, Steiner J, Pasternack N, Li W, Maric D, Safavi F, Horkayne-Szakaly I, Jones R, Stram MN, Moncur JT, Hefti M, Folkerth RD, Nath A. Neurovascular injury with complement activation and inflammation in COVID-19. Brain. 2022 Jul 5:awac151. doi: 10.1093/brain/awac151. Epub ahead of print. PMID: 35788639; PMCID: PMC9278212. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9278212/ (Full text)

Preparing for the long-haul: Autonomic complications of COVID-19

Abstract:

As global numbers of COVID-19 grow, chronic neurological symptoms, including those of autonomic dysfunction, are being reported with increasing frequency. Mounting evidence suggests that many patients experience chronic and sometimes debilitating symptoms long after their acute infectious period, leading to the new diagnostic category of post-acute COVID syndrome. Many symptoms of post-acute COVID syndrome appear autonomic in nature, suggesting that autonomic impairment may play a central role in the underlying pathophysiology. In this review, we discuss the autonomic symptoms and manifestations of post-acute COVID syndrome, potential mechanisms involved, and future directions for a better understanding of this novel condition.

Source: Larsen NW, Stiles LE, Miglis MG. Preparing for the long-haul: Autonomic complications of COVID-19. Auton Neurosci. 2021;235:102841. doi:10.1016/j.autneu.2021.102841  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8254396/ (Full text)

Pathophysiology and mechanism of long COVID: a comprehensive review

Abstract:

Background: After almost 2 years of fighting against SARS-CoV-2 pandemic, the number of patients enduring persistent symptoms long after acute infection is a matter of concern. This set of symptoms was referred to as “long COVID”, and it was defined more recently as “Post COVID-19 condition” by the World health Organization (WHO). Although studies have revealed that long COVID can manifest whatever the severity of inaugural illness, the underlying pathophysiology is still enigmatic.

Aim: To conduct a comprehensive review to address the putative pathophysiology underlying the persisting symptoms of long COVID.

Method: We searched 11 bibliographic databases (Cochrane Library, JBI EBP Database, Medline, Embase, PsycInfo, CINHAL, Ovid Nursing Database, Journals@Ovid, SciLit, EuropePMC, and CoronaCentral). We selected studies that put forward hypotheses on the pathophysiology, as well as those that encompassed long COVID patients in their research investigation.

Results: A total of 98 articles were included in the systematic review, 54 of which exclusively addressed hypotheses on pathophysiology, while 44 involved COVID patients. Studies that included patients displayed heterogeneity with respect to the severity of initial illness, timing of analysis, or presence of a control group. Although long COVID likely results from long-term organ damage due to acute-phase infection, specific mechanisms following the initial illness could contribute to the later symptoms possibly affecting many organs. As such, autonomic nervous system damage could account for many symptoms without clear evidence of organ damage. Immune dysregulation, auto-immunity, endothelial dysfunction, occult viral persistence, as well as coagulation activation are the main underlying pathophysiological mechanisms so far.

Conclusion: Evidence on why persistent symptoms occur is still limited, and available studies are heterogeneous. Apart from long-term organ damage, many hints suggest that specific mechanisms following acute illness could be involved in long COVID symptoms.

KEY MESSAGES:

  • Long-COVID is a multisystem disease that develops regardless of the initial disease severity. Its clinical spectrum comprises a wide range of symptoms.
  • The mechanisms underlying its pathophysiology are still unclear. Although organ damage from the acute infection phase likely accounts for symptoms, specific long-lasting inflammatory mechanisms have been proposed, as well.
  • Existing studies involving Long-COVID patients are highly heterogeneous, as they include patients with various COVID-19 severity levels and different time frame analysis, as well.

Source: Castanares-Zapatero D, Chalon P, Kohn L, Dauvrin M, Detollenaere J, Maertens de Noordhout C, Primus-de Jong C, Cleemput I, Van den Heede K. Pathophysiology and mechanism of long COVID: a comprehensive review. Ann Med. 2022 Dec;54(1):1473-1487. doi: 10.1080/07853890.2022.2076901. PMID: 35594336; PMCID: PMC9132392. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9132392/ (Full text)

Long COVID: A proposed hypothesis-driven model of viral persistence for the pathophysiology of the syndrome

Abstract:

Background: Long COVID (coronavirus disease 2019) syndrome includes a group of patients who, after infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), exhibit lingering mild-to-moderate symptoms and develop medical complications that can have lasting health problems. In this report, we propose a model for the pathophysiology of the long COVID presentation based on increased proinflammatory cytokine production that results from the persistence of the SARS-CoV-2 virus or one of its molecular components. Associated with this hyperproduction of inflammatory cytokines is a heightened activity of nuclear factor κ B (NF-κB) and p38 mitogen-activated protein kinase signaling pathways that regulate cytokine production.

Objective: The purpose of the present report was to review the causes of long COVID syndrome and suggest ways that can provide a basis for a better understanding of the clinical symptomatology for the of improved diagnostic and therapeutic procedures for the condition.

Methods: Extensive research was conducted in medical literature data bases by applying terms such as “long COVID” associated with “persistence of the SARS-CoV-2 virus” “spike protein’ “COVID-19” and “biologic therapies.”

Results and Conclusions: In this model of the long COVID syndrome, the persistence of SARS-CoV-2 is hypothesized to trigger a dysregulated immune system with subsequent heightened release of proinflammatory cytokines that lead to chronic low-grade inflammation and multiorgan symptomatology. The condition seems to have a genetic basis, which predisposes individuals to have a diminished immunologic capacity to completely clear the virus, with residual parts of the virus persisting. This persistence of virus and resultant hyperproduction of proinflammatory cytokines are proposed to form the basis of the syndrome.

Source: Buonsenso D, Piazza M, Boner AL, Bellanti JA. Long COVID: A proposed hypothesis-driven model of viral persistence for the pathophysiology of the syndrome. Allergy Asthma Proc. 2022 May 1;43(3):187-193. doi: 10.2500/aap.2022.43.220018. PMID: 35524358. https://pubmed.ncbi.nlm.nih.gov/35524358/ https://www.ingentaconnect.com/content/ocean/aap/2022/00000043/00000003/art00003;jsessionid=pp9ea7gev7kv.x-ic-live-01#  (Full text available as download)

Cardiovascular impairment in long covid one year post-sars-cov-2 infection

Background: Long Covid is associated with multi-organ inflammation, hypercoagulability, and several symptoms (fatigue, dyspnoea etc). Varying levels of cardiac involvement have been reported by cardiac magnetic resonance (CMR). We now describe longitudinal cardiovascular impairment in patients with Long Covid at 6 and 12 months post-SARS-CoV-2 infection.

Methods: 524 participants with Long Covid underwent a baseline scan at 6 months post infection (ClinicalTrials.gov: NCT04369807) and were rescanned 12 months post-infection if abnormal findings were reported at baseline. CMR (T1 and T2, cardiac mass, volumes, function, and strain), along with multi-organ MRI and blood samples were collected. Cardiovascular impairment was defined as one or more of: low left ventricular ejection fraction (LVEF), high left ventricular end diastolic volume (LVEDV), elevated native T1 in 3 or more cardiac segments. A significant longitudinal change was reported if greater than the repeatability coefficients derived from a population of 92 healthy controls.

Results: In 70 patients with cardiovascular impairment and Long Covid at baseline, 48 had complete paired data at 1 year, and of those 54% had not fully resolved. 19 (27%) patients with cardiovascular impairment had required hospitalization for acute COVID-19. Troponin or BNP were not predictive of CMR findings; however, hospitalization at the acute stage, male sex, kidney fibroinflammation and serum bicarbonate were. Individual symptoms were not specific to cardiovascular impairment or disease course.

Conclusion: CMR shows that cardiovascular impairment persists in Long Covid in some patients beyond 12 months post infection; however, this impairment may have pre-existing origin. Although there is an association with acute COVID-19 hospitalisation, male gender and high serum bicarbonate were predictive of cardiovascular impairment, subtypes of disease (based on symptoms, examination, and investigations) are yet to be established. Therefore, interventional trials with pre-specified subgroup analysis are required to inform therapeutic options.

Source: Roca-Fernandez A, Wamil M, Telford A, et al. CARDIOVASCULAR IMPAIRMENT IN LONG COVID ONE YEAR POST-SARS-COV-2 INFECTION. J Am Coll Cardiol. 2022 Mar, 79 (9_Supplement) 1312. https://doi.org/10.1016/S0735-1097(22)02303-8

Long COVID: post-acute sequelae of COVID-19 with a cardiovascular focus

Abstract:

Emerging as a new epidemic, long COVID or post-acute sequelae of coronavirus disease 2019 (COVID-19), a condition characterized by the persistence of COVID-19 symptoms beyond 3 months, is anticipated to substantially alter the lives of millions of people globally. Cardiopulmonary symptoms including chest pain, shortness of breath, fatigue, and autonomic manifestations such as postural orthostatic tachycardia are common and associated with significant disability, heightened anxiety, and public awareness. A range of cardiovascular (CV) abnormalities has been reported among patients beyond the acute phase and include myocardial inflammation, myocardial infarction, right ventricular dysfunction, and arrhythmias.

Pathophysiological mechanisms for delayed complications are still poorly understood, with a dissociation seen between ongoing symptoms and objective measures of cardiopulmonary health. COVID-19 is anticipated to alter the long-term trajectory of many chronic cardiac diseases which are abundant in those at risk of severe disease.

In this review, we discuss the definition of long COVID and its epidemiology, with an emphasis on cardiopulmonary symptoms. We further review the pathophysiological mechanisms underlying acute and chronic CV injury, the range of post-acute CV sequelae, and impact of COVID-19 on multiorgan health. We propose a possible model for referral of post-COVID-19 patients to cardiac services and discuss future directions including research priorities and clinical trials that are currently underway to evaluate the efficacy of treatment strategies for long COVID and associated CV sequelae.

Source: Raman B, Bluemke DA, Lüscher TF, Neubauer S. Long COVID: post-acute sequelae of COVID-19 with a cardiovascular focus. Eur Heart J. 2022 Feb 18:ehac031. doi: 10.1093/eurheartj/ehac031. Epub ahead of print. PMID: 35176758. https://academic.oup.com/eurheartj/advance-article/doi/10.1093/eurheartj/ehac031/6529562 (Full text)

Assessment and Management of Long COVID

Abstract:

Almost two years into the pandemic, the scientific and healthcare communities continue to learn a great deal regarding COVID-19, the disease produced by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Broad variability during acute COVID-19 infection is seen, ranging from asymptomatic presentation to death. The vast majority of individuals who develop COVID-19 return to their pre-COVID-19 baseline within several weeks.

However, a portion of patients will develop a post-COVID-19 syndrome of persistent cognitive, somatic, and behavioral symptoms. This syndrome, designated as post-acute sequelae of SARS-CoV-2 infection, is more commonly known as long COVID. The objectives of this paper are to inform psychologists regarding our current understanding of the underlying pathophysiology of COVID-19, review criteria for range of severity during acute illness, present clinical manifestations of long haul phenomena, and discuss the emerging literature base of evidence-based treatment and management approaches.

Source: Rivas-Vazquez, R.A., Rey, G., Quintana, A. et al. Assessment and Management of Long COVID. J Health Serv Psychol 48, 21–30 (2022). https://doi.org/10.1007/s42843-022-00055-8  (Full study)