Fenofibrate for COVID-19 and related complications as an approach to improve treatment outcomes: the missed key for Holy Grail

Cyclin-dependent kinase 5 (CDK5) inhibitors in Parkinson disease

Cyclin-dependent kinase 5 (Cdk5) is a protein expressed in postmitotic neurons in the central nervous system (CNS). Cdk5 is activated by p35 and p39 which are neuron regulatory subunits. Cdk5/p35 complex is activated by calpain protease to form Cdk5/p35 which has a neuroprotective effect by regulating the synaptic plasticity and memory functions. However, exaggerated Cdk5 is implicated in different types of neurodegenerative diseases including Parkinson disease (PD). Therefore, modulation of Cdk5 signalling may mitigate PD neuropathology. Therefore, the aim of the present review was to discuss the critical role of Cdk5 in the pathogenesis of PD, and how Cdk5 inhibitors are effectual in the management of PD. In conclusion, overactivated Cdk5 is involved the development of neurodegeneration, and Cdk5/calpain inhibitors such as statins, metformin, fenofibrates and rosiglitazone can attenuate the progression of PD neuropathology.

Multimorbidity in middle-aged women and COVID-19: binary data clustering for unsupervised binning of rare multimorbidity features and predictive modeling

BACKGROUND

Multimorbidity is typically associated with deficient health-related quality of life in mid-life, and the likelihood of developing multimorbidity in women is elevated. We address the issue of data sparsity in non-prevalent features by clustering the binary data of various rare medical conditions in a cohort of middle-aged women. This study aims to enhance understanding of how multimorbidity affects COVID-19 severity by clustering rare medical conditions and combining them with prevalent features for predictive modeling. The insights gained can guide the development of targeted interventions and improved management strategies for individuals with multiple health conditions.

METHODS

The study focuses on a cohort of 4477 female patients, (aged 45-60) in Piedmont, Italy, and utilizes their multimorbidity data prior to the COVID-19 pandemic from their medical history from 2015 to 2019. The COVID-19 severity is determined by the hospitalization status of the patients from February to May 2020. Each patient profile in the dataset is depicted as a binary vector, where each feature denotes the presence or absence of a specific multimorbidity condition. By clustering the sparse medical data, newly engineered features are generated as a bin of features, and they are combined with the prevalent features for COVID-19 severity predictive modeling.

RESULTS

From sparse data consisting of 174 input features, we have created a low-dimensional feature matrix of 17 features. Machine Learning algorithms are applied to the reduced sparsity-free data to predict the Covid-19 hospital admission outcome. The performance obtained for the corresponding models are as follows: Logistic Regression (accuracy 0.72, AUC 0.77, F1-score 0.69), Linear Discriminant Analysis (accuracy 0.7, AUC 0.77, F1-score 0.67), and Ada Boost (accuracy 0.7, AUC 0.77, F1-score 0.68).

CONCLUSION

Mapping higher-dimensional data to a low-dimensional space can result in information loss, but reducing sparsity can be beneficial for Machine Learning modeling due to improved predictive ability. In this study, we addressed the issue of data sparsity in electronic health records and created a model that incorporates both prevalent and rare medical conditions, leading to more accurate and effective predictive modeling. The identification of complex associations between multimorbidity and the severity of COVID-19 highlights potential areas of focus for future research, including long COVID and intervention efforts.

Therapeutic Potential Effect of Glycogen Synthase Kinase 3 Beta (GSK-3β) Inhibitors in Parkinson Disease: Exploring an Overlooked Avenue

Parkinson's disease (PD) is a progressive neurodegenerative disease of the brain due to degeneration of dopaminergic neurons in the substantia nigra (SN). Glycogen synthase kinase 3 beta (GSK-3β) is implicated in the pathogenesis of PD. Therefore, the purpose of the present review was to revise the mechanistic role of GSK-3β in PD neuropathology, and how GSK-3β inhibitors affect PD neuropathology. GSK-3 is a conserved threonine/serine kinase protein that is intricate in the regulation of cellular anabolic and catabolic pathways by modulating glycogen synthase. Over-expression of GSK-3β is also interconnected with the development of different neurodegenerative diseases. However, the underlying mechanism of GSK-3β in PD neuropathology is not fully clarified. Over-expression of GSK-3β induces the development of PD by triggering mitochondrial dysfunction and oxidative stress in the dopaminergic neurons of the SN. NF-κB and NLRP3 inflammasome are activated in response to dysregulated GSK-3β in PD leading to progressive neuronal injury. Higher expression of GSK-3β in the early stages of PD neuropathology might contribute to the reduction of neuroprotective brain-derived neurotrophic factor (BDNF). Thus, GSK-3β inhibitors may be effective in PD by reducing inflammatory and oxidative stress disorders which are associated with degeneration of dopaminergic in the SN.

Role of fenofibrate in multiple sclerosis

Multiple sclerosis (MS) is the most frequent inflammatory and demyelinating disease of the central nervous system (CNS). The underlying pathophysiology of MS is the destruction of myelin sheath by immune cells. The formation of myelin plaques, inflammation, and injury of neuronal myelin sheath characterizes its neuropathology. MS plaques are multiple focal regions of demyelination disseminated in the brain's white matter, spinal cords, deep grey matter, and cerebral cortex. Fenofibrate is a peroxisome proliferative activated receptor alpha (PPAR-α) that attenuates the inflammatory reactions in MS. Fenofibrate inhibits differentiation of Th17 by inhibiting the expression of pro-inflammatory signaling. According to these findings, this review intended to illuminate the mechanistic immunoinflammatory role of fenofibrate in mitigating MS neuropathology. In conclusion, fenofibrate can attenuate MS neuropathology by modulating different pathways, including oxidative stress, autophagy, mitochondrial dysfunction, inflammatory-signaling pathways, and neuroinflammation.

The possible role of nuclear factor erythroid-2-related factor 2 activators in the management of Covid-19

COVID-19 is caused by a novel SARS-CoV-2 leading to pulmonary and extra-pulmonary manifestations due to oxidative stress (OS) development and hyperinflammation. COVID-19 is primarily asymptomatic though it may cause acute lung injury (ALI), acute respiratory distress syndrome (ARDS), systemic inflammation, and thrombotic events in severe cases. SARS-CoV-2-induced OS triggers the activation of different signaling pathways, which counterbalances this complication. One of these pathways is nuclear factor erythroid 2-related factor 2 (Nrf2), which induces a series of cellular interactions to mitigate SARS-CoV-2-mediated viral toxicity and OS-induced cellular injury. Nrf2 pathway inhibits the expression of pro-inflammatory cytokines and the development of cytokine storm in COVID-19. Therefore, Nrf2 activators may play an essential role in reducing SARS-CoV-2 infection-induced inflammation by suppressing NLRP3 inflammasome in COVID-19. Furthermore, Nrf2 activators can attenuate endothelial dysfunction (ED), renin-angiotensin system (RAS) dysregulation, immune thrombosis, and coagulopathy. Thus this mini-review tries to clarify the possible role of the Nrf2 activators in the management of COVID-19. Nrf2 activators could be an effective therapeutic strategy in the management of Covid-19. Preclinical and clinical studies are recommended in this regard.

SARS-CoV-2 infection and dysregulation of nuclear factor erythroid-2-related factor 2 (Nrf2) pathway

Coronavirus disease 2019 (COVID-19) is a recent pandemic caused by a novel severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) leading to pulmonary and extra-pulmonary manifestations due to the development of oxidative stress (OS) and hyperinflammation. The underlying cause for OS and hyperinflammation in COVID-19 may be related to the inhibition of nuclear factor erythroid 2-related factor 2 (Nrf2), a master regulator of antioxidative responses and cellular homeostasis. The Nrf2 pathway inhibits the expression of pro-inflammatory cytokines and the development of cytokine storm and OS in COVID-19. Nrf2 activators can attenuate endothelial dysfunction (ED), renin-angiotensin system (RAS) dysregulation, immune thrombosis, and coagulopathy. Hence, this review aimed to reveal the potential role of the Nrf2 pathway and its activators in the management of COVID-19. As well, we tried to revise the mechanistic role of the Nrf2 pathway in COVID-19.

Receptor-dependent effects of sphingosine-1-phosphate (S1P) in COVID-19: the black side of the moon

Severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) infection leads to hyper-inflammation and amplified immune response in severe cases that may progress to cytokine storm and multi-organ injuries like acute respiratory distress syndrome and acute lung injury. In addition to pro-inflammatory cytokines, different mediators are involved in SARS-CoV-2 pathogenesis and infection, such as sphingosine-1-phosphate (S1P). S1P is a bioactive lipid found at a high level in plasma, and it is synthesized from sphingomyelin by the action of sphingosine kinase. It is involved in inflammation, immunity, angiogenesis, vascular permeability, and lymphocyte trafficking through G-protein coupled S1P receptors. Reduction of the circulating S1P level correlates with COVID-19 severity. S1P binding to sphingosine-1-phosphate receptor 1 (S1PR1) elicits endothelial protection and anti-inflammatory effects during SARS-CoV-2 infection, by limiting excessive INF-α response and hindering mitogen-activated protein kinase and nuclear factor kappa B action. However, binding to S1PR2 opposes the effect of S1PR1 with vascular inflammation, endothelial permeability, and dysfunction as the concomitant outcome. This binding also promotes nod-like receptor pyrin 3 (NLRP3) inflammasome activation, causing liver inflammation and fibrogenesis. Thus, higher expression of macrophage S1PR2 contributes to the activation of the NLRP3 inflammasome and the release of pro-inflammatory cytokines. In conclusion, S1PR1 agonists and S1PR2 antagonists might effectively manage COVID-19 and its severe effects. Further studies are recommended to elucidate the potential conflict in the effects of S1P in COVID-19.

Role of sphingosine 1-phosphate (S1P) in sepsis-associated intestinal injury

Sphingosine-1-phosphate (S1P) is a widespread lipid signaling molecule that binds to five sphingosine-1-phosphate receptors (S1PRs) to regulate downstream signaling pathways. Sepsis can cause intestinal injury and intestinal injury can aggravate sepsis. Thus, intestinal injury and sepsis are mutually interdependent. S1P is more abundant in intestinal tissues as compared to other tissues, exerts anti-inflammatory effects, promotes immune cell trafficking, and protects the intestinal barrier. Despite the clinical importance of S1P in inflammation, with a very well-defined mechanism in inflammatory bowel disease, their role in sepsis-induced intestinal injury has been relatively unexplored. In addition to regulating lymphocyte exit, the S1P-S1PR pathway has been implicated in the gut microbiota, intestinal epithelial cells (IECs), and immune cells in the lamina propria. This review mainly elaborates on the physiological role of S1P in sepsis, focusing on intestinal injury. We introduce the generation and metabolism of S1P, emphasize the maintenance of intestinal barrier homeostasis in sepsis, and the protective effect of S1P in the intestine. We also review the link between sepsis-induced intestinal injury and S1P-S1PRs signaling, as well as the underlying mechanisms of action. Finally, we discuss how S1PRs affect intestinal function and become targets for future drug development to improve the translational capacity of preclinical studies to the clinic.

Potential role of tirzepatide towards Covid-19 infection in diabetic patients: a perspective approach

In Covid-19, variations in fasting blood glucose are considered a distinct risk element for a bad prognosis and outcome in Covid-19 patients. Tirazepatide (TZT), a dual glucagon-like peptide-1 (GLP-1)and glucose-dependent insulinotropic polypeptide (GIP) receptor agonist may be effective in managing Covid-19-induced hyperglycemia in diabetic and non-diabetic patients. The beneficial effect of TZT in T2DM and obesity is related to direct activation of GIP and GLP-1 receptors with subsequent improvement of insulin sensitivity and reduction of body weight. TZT improves endothelial dysfunction (ED) and associated inflammatory changes through modulation of glucose homeostasis, insulin sensitivity, and pro-inflammatory biomarkers release. TZT, through activation of the GLP-1 receptor, may produce beneficial effects against Covid-19 severity since GLP-1 receptor agonists (GLP-1RAs) have anti-inflammatory and pulmoprotective implications in Covid-19. Therefore, GLP-1RAs could effectively treat severely affected Covid-19 diabetic and non-diabetic patients. Notably, using GLP-1RAs in T2DM patients prevents glucose variability, a common finding in Covid-19 patients. Therefore, GLP-1RAs like TZT could be a therapeutic strategy in T2DM patients with Covid-19 to prevent glucose variability-induced complications. In Covid-19, the inflammatory signaling pathways are highly activated, resulting in hyperinflammation. GLP-1RAs reduce inflammatory biomarkers like IL-6, CRP, and ferritin in Covid-19 patients. Therefore, GLP-1RAs like TZ may be effective in Covid-19 patients by reducing the inflammatory burden. The anti-obesogenic effect of TZT may reduce Covid-19 severity by ameliorating body weight and adiposity. Furthermore, Covid-19 may induce substantial alterations in gut microbiota. GLP-1RA preserves gut microbiota and prevents intestinal dysbiosis. Herein, TZT, like other GLP-1RA, may attenuate Covid-19-induced gut microbiota alterations and, by this mechanism, may mitigate intestinal inflammation and systemic complications in Covid-19 patients with either T2DM or obesity. As opposed to that, glucose-dependent insulinotropic polypeptide (GIP) was reduced in obese and T2DM patients. However, activation of GIP-1R by TZT in T2DM patients improves glucose homeostasis. Thus, TZT, through activation of both GIP and GLP-1, may reduce obesity-mediated inflammation. In Covid-19, GIP response to the meal is impaired, leading to postprandial hyperglycemia and abnormal glucose homeostasis. Therefore, using TZT in severely affected Covid-19 patients may prevent the development of glucose variability and hyperglycemia-induced oxidative stress. Moreover, exaggerated inflammatory disorders in Covid-19 due to the release of pro-inflammatory cytokines like IL-1β, IL-6, and TNF-α may lead to systemic inflammation and cytokine storm development. Besides, GIP-1 inhibits expression of IL-1β, IL-6, MCP-1, chemokines and TNF-α. Therefore, using GIP-1RA like TZT may inhibit the onset of inflammatory disorders in severely affected Covid-19 patients. In conclusion, TZT, through activation of GLP-1 and GIP receptors, may prevent SARS-CoV-2-induced hyperinflammation and glucose variability in diabetic and non-diabetic patients.

Covid-19 a triggering factor of autoimmune and multi-inflammatory diseases

SARS-CoV-2 virus has attracted a lot of attention globally due to the autoimmune and inflammatory processes that were observed during the development of Covid-19 disease. Excessive activation of immune response and triggering of autoantibodies synthesis as well as an excessive synthesis of inflammatory cytokines and the onset of cytokine storm has a vital role in the disease outcome and the occurring autoimmune complications. This scenario is reminiscent of infiltration of lymphocytes and monocytes in specific organs and the increased production of autoantibodies and chemoattractants noted in other inflammatory and autoimmune diseases. The main goal of this study is to investigate the complex inflammatory processes that occur in Covid-19 disease and to find similarities with other inflammatory diseases such as multiple sclerosis (MS), acute respiratory distress syndrome (ARDS), rheumatoid arthritis (RA) and Kawasaki syndrome to advance existing diagnostic and therapeutic protocols. The therapy with Interferon-gamma (IFN-γ) and the use of S1P receptor modulators showed promising results. However, there are many unknowns about these mechanisms and possible novel therapies. Therefore, the inflammation and autoimmunity triggered by Covid-19 should be further investigated to improve existing diagnostic procedures and therapeutic protocols for Covid-19.

Mixed storm in SARS-CoV-2 infection: A narrative review and new term in the Covid-19 era

Coronavirus disease 2019 (Covid-19) is caused by a novel severe acute respiratory syndrome coronavirus virus type 2 (SARS-CoV-2) leading to the global pandemic worldwide. Systemic complications in Covid-19 are mainly related to the direct SARS-CoV-2 cytopathic effects, associated hyperinflammation, hypercytokinemia, and the development of cytokine storm (CS). As well, Covid-19 complications are developed due to the propagation of oxidative and thrombotic events which may progress to a severe state called oxidative storm and thrombotic storm (TS), respectively. In addition, inflammatory and lipid storms are also developed in Covid-19 due to the activation of inflammatory cells and the release of bioactive lipids correspondingly. Therefore, the present narrative review aimed to elucidate the interrelated relationship between different storm types in Covid-19 and the development of the mixed storm (MS). In conclusion, SARS-CoV-2 infection induces various storm types including CS, inflammatory storm, lipid storm, TS and oxidative storm. These storms are not developing alone since there is a close relationship between them. Therefore, the MS seems to be more appropriate to be related to severe Covid-19 than CS, since it develops in Covid-19 due to the intricate interface between reactive oxygen species, proinflammatory cytokines, complement activation, coagulation disorders, and activated inflammatory signaling pathway.

Treating COVID-19: Targeting the Host Response, Not the Virus

In low- and middle-income countries (LMICs), inexpensive generic drugs like statins, ACE inhibitors, and ARBs, especially if used in combination, might be the only practical way to save the lives of patients with severe COVID-19. These drugs will already be available in all countries on the first pandemic day. Because they target the host response to infection instead of the virus, they could be used to save lives during any pandemic. Observational studies show that inpatient statin treatment reduces 28–30-day mortality but randomized controlled trials have failed to show this benefit. Combination treatment has been tested for antivirals and dexamethasone but, with the exception of one observational study in Belgium, not for inexpensive generic drugs. Future pandemic research must include testing combination generic drug treatments that could be used in LMICs.

Peroxisome Proliferator-Activated Receptor-Targeted Therapies: Challenges upon Infectious Diseases

Peroxisome proliferator-activated receptors (PPARs) α, β, and γ are nuclear receptors that orchestrate the transcriptional regulation of genes involved in a variety of biological responses, such as energy metabolism and homeostasis, regulation of inflammation, cellular development, and differentiation. The many roles played by the PPAR signaling pathways indicate that PPARs may be useful targets for various human diseases, including metabolic and inflammatory conditions and tumors. Accumulating evidence suggests that each PPAR plays prominent but different roles in viral, bacterial, and parasitic infectious disease development. In this review, we discuss recent PPAR research works that are focused on how PPARs control various infections and immune responses. In addition, we describe the current and potential therapeutic uses of PPAR agonists/antagonists in the context of infectious diseases. A more comprehensive understanding of the roles played by PPARs in terms of host-pathogen interactions will yield potential adjunctive personalized therapies employing PPAR-modulating agents.

The role of peroxisome proliferator-activated receptors in the modulation of hyperinflammation induced by SARS-CoV-2 infection: A perspective for COVID-19 therapy

Coronavirus disease 2019 (COVID-19) is a severe respiratory disease caused by infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that affects the lower and upper respiratory tract in humans. SARS-CoV-2 infection is associated with the induction of a cascade of uncontrolled inflammatory responses in the host, ultimately leading to hyperinflammation or cytokine storm. Indeed, cytokine storm is a hallmark of SARS-CoV-2 immunopathogenesis, directly related to the severity of the disease and mortality in COVID-19 patients. Considering the lack of any definitive treatment for COVID-19, targeting key inflammatory factors to regulate the inflammatory response in COVID-19 patients could be a fundamental step to developing effective therapeutic strategies against SARS-CoV-2 infection. Currently, in addition to well-defined metabolic actions, especially lipid metabolism and glucose utilization, there is growing evidence of a central role of the ligand-dependent nuclear receptors and peroxisome proliferator-activated receptors (PPARs) including PPARα, PPARβ/δ, and PPARγ in the control of inflammatory signals in various human inflammatory diseases. This makes them attractive targets for developing therapeutic approaches to control/suppress the hyperinflammatory response in patients with severe COVID-19. In this review, we (1) investigate the anti-inflammatory mechanisms mediated by PPARs and their ligands during SARS-CoV-2 infection, and (2) on the basis of the recent literature, highlight the importance of PPAR subtypes for the development of promising therapeutic approaches against the cytokine storm in severe COVID-19 patients.

Pregnancy and COVID-19: high or low risk of vertical transmission

Coronavirus disease 19 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome 2 (SARS-CoV-2). Throughout the pandemic, evidence on the effects of COVID-19 during pregnancy has been inadequate due to the limited number of studies published. Therefore, the objective of this systematic review was to evaluate current literature regarding the effects of COVID-19 during pregnancy and establish pregnancy outcomes and vertical and perinatal transmission during pregnancy. Multiple databases were searched, including Embase, Medline, Web of Science, Scopus, and Cochrane Central Register of Control Clinical Trials, using the following keywords: [Pregnancy] AND [COVID-19 OR SARS-CoV-2 OR nCoV-19] OR [Perinatal transmission, Vertical transmission (VT), Pregnancy complications], [Pregnancy] AND [Hyperinflammation OR Cytokine storm]. We excluded in vitro and experimental studies, but also ex-vivo and animal study methods. To exclude the risk of bias during data collection and interpretation, all included studies were peer-reviewed publications. This review is estimated to tabulate the study intervention characteristics and compare them against the planned groups for each synthesis. Our findings showed that pregnant women are commonly susceptible to respiratory viral infections and severe pneumonia due to physiological immune suppression and pregnancy-induced changes. VT of SARS-CoV-2 infection during pregnancy is associated with a great deal of controversy and conflict. However, there is still no robust clinical evidence of VT. Furthermore, the clinical presentation and management of COVID-19 during pregnancy are nearly identical to those of non-pregnant women. Finally, chloroquine and remdesivir are the only two drugs evaluated as adequate for the management of COVID-19 during pregnancy.

Role of Neuropilin 1 in COVID-19 Patients with Acute Ischemic Stroke

Severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) infection can trigger the adaptive and innate immune responses, leading to uncontrolled inflammatory reactions and associated local and systematic tissue damage, along with thromboembolic disorders that may increase the risk of acute ischemic stroke (AIS) in COVID-19 patients. The neuropilin (NRP-1) which is a co-receptor for the vascular endothelial growth factor (VEGF), integrins, and plexins, is involved in the pathogenesis of AIS. NRP-1 is also regarded as a co-receptor for the entry of SARS-CoV-2 and facilitates its entry into the brain through the olfactory epithelium. NRP-1 is regarded as a cofactor for binding of SARS-CoV-2 with angiotensin-converting enzyme 2 (ACE2), since the absence of ACE2 reduces SARS-CoV-2 infectivity even in presence of NRP-1. Therefore, the aim of the present study was to clarify the potential role of NRP-1 in COVID-19 patients with AIS. SARS-CoV-2 may transmit to the brain through NRP-1 in the olfactory epithelium of the nasal cavity, leading to different neurological disorders, and therefore about 45% of COVID-19 patients had neurological manifestations. NRP-1 has the potential capability to attenuate neuroinflammation, blood–brain barrier (BBB) permeability, cerebral endothelial dysfunction (ED), and neuronal dysfunction that are uncommon in COVID-19 with neurological involvement, including AIS. Similarly, high NRP-1 serum level is linked with ED, oxidative stress, and the risk of pulmonary thrombosis in patients with severe COVID-19, suggesting a compensatory mechanism to overcome immuno-inflammatory disorders. In conclusion, NRP-1 has an important role in the pathogenesis of COVID-19 and AIS, and could be the potential biomarker linking the development of AIS in COVID-19. The present findings cannot provide a final conclusion, and thus in silico, experimental, in vitro, in vivo, preclinical, and clinical studies are recommended to confirm the potential role of NRP-1 in COVID-19, and to elucidate the pharmacological role of NRP-1 receptor agonists and antagonists in COVID-19.