Pirfenidone and post-Covid-19 pulmonary fibrosis: invoked again for realistic goals

Discovery of a series of novel 3-sulfonamido benzoic acid derivatives as promising P2Y14R antagonists for acute lung injury

The P2Y14 receptor (P2Y14R) has been identified as a potential target for various inflammatory diseases, particularly acute lung injury (ALI). However, very few P2Y14R antagonists have been reported so far, especially those with innovative scaffolds. And none have entered clinical trials due to the shortcomings of low antagonistic activity and poor druggability. Herein, we designed, synthesized and evaluated a series of 3-sulfonamido benzoic acid derivatives as P2Y14R antagonists with novel scaffolds based on PPTN, which is considered to be the most potent P2Y14R antagonist. Among them, compound 25l (IC50 = 5.6 ± 0.3 nM) emerged as the most potent P2Y14R antagonist, exhibiting not only significantly better antagonistic activity compared to the rest but also superior binding affinity to P2Y14R over PPTN. Moreover, the solubility and pharmacokinetic properties of compound 25l were proven to be better than those of PPTN. The anti-inflammatory effect of compound 25l was investigated using an LPS-induced mouse ALI model. The results showed that compound 25l significantly reduced the inflammatory response in lung tissues and the levels of proinflammatory cytokines (IL-1β, IL-6, and TNF-α) induced by LPS. Therefore, compound 25l, with its potent P2Y14R antagonistic activity and favorable druggability, is a promising candidate for further investigation as an anti-inflammatory drug.

Insight into the efficacy and safety of pirfenidone: The treatment of idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) has a poor prognosis if left untreated; therefore, early treatment with pirfenidone is crucial. Lei et al conducted a retrospective analysis to evaluate the effectiveness of early pirfenidone treatment on lung function in 113 patients with IPF. In addition to other research, pirfenidone has demonstrated efficacy in patients at all stages of IPF once correct diagnosis has been made. In advanced IPF, we include the requirement for pirfenidone. Therefore, it is essential to choose an appropriate method of administration method, such as inhalation. This may circumvent the drawbacks of the high cost and possible adverse effects of this drug.

Post-COVID-19 lung disease: utility of biochemical and imaging markers in uncovering residual lung inflammation and monitoring anti-inflammatory therapy, a prospective study

PURPOSE

Post-COVID-19 lung disease (PCLD) is a significant concern following the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. PCLD encompasses persistent debilitating respiratory symptoms and radiological changes beyond the acute disease phase. It highlights the ongoing search to identify and manage lingering diseases. This prospective study utilizes F18-Fludeoxyglucose (FDG) PET/CT to identify residual inflammatory lung lesions in PCLD. Treatment response was assessed after anti-inflammatory and antifibrotic therapies.

MATERIALS AND METHODS

Thirty patients post-severe COVID-19 pneumonia enrolled. They underwent baseline 18F-FDG PET/CT scans to unveil residual lung inflammation lesions on FDG and CT. They received antifibrotic (Pirfenidone) and anti-inflammatory (Methylprednisolone) drugs for 6-12 weeks. They were followed up for clinical, biochemical, and imaging treatment responses.

RESULTS

Baseline 18F-FDG PET/CT revealed ongoing lung inflammation in all PCLD (mean SUVmax: 3.8 ± 2.3 and number of segments: 8±3 ). The mean CT severity score was 17.7 ± 3.4 with moderate (n = 16) or severe (n = 14) disease involvement. Mild, moderate, and severe 18F-FDG PET/CT categories were noted in the 8, 14, and 8 patients, respectively. Following treatment, a PET scan showed a significant decrease in disease extent (segments) and severity (FDG uptake) and an improvement in disease grading on imaging (97% of patients). In PET concordance, there was a significant clinical and radiological improvement with a fall in inflammatory markers (p < 0.005). Serum Ferritin and total leukocyte counts were significantly associated with PCLD severity on 18F-FDG PET/CT(p < 0.05).

CONCLUSION

This prospective study identifies and quantifies ongoing significant residual lung inflammation in PCLD on 18F-FDG PET/CT. Anti-inflammatory and antifibrotic drug therapy led to clinical and radiological improvement. 18F-FDG PET/CT as a non-invasive biomarker helped manage and follow up PCLD patients.

CLINICAL TRIAL NUMBER

Not applicable.

Role of Fibroblast Growth Factors in Neurological Disorders: Insight into Therapeutic Approaches and Molecular Mechanisms

In the last few decades, the incidence and progression of neurological disorders have consistently increased, which mainly occur due to environmental pollution, genetic abnormalities, and modern lifestyles. Several case reports suggested that these factors enhanced oxidative stress, mitochondrial dysfunction, inflammation, and apoptosis, leading to neurological disease. The pathophysiology of neurological disorders is still not understood, mainly due to the diversity within affected populations. Existing treatment options primarily provide symptomatic relief but frequently come with considerable side effects, including depression, anxiety, and restlessness. Fibroblast growth factors (FGFs) are key signalling molecules regulating various cellular functions, including cell proliferation, differentiation, electrical excitability, and injury responses. Hence, several investigations claimed a relationship between FGFs and neurological disorders, and their findings indicated that they could be used as therapeutic targets for neurological disorders. The FGFs are reported to activate various signalling pathways, including Ras/MAPK/PI3k/Akt, and downregulate the GSK-3β/NF-κB pathways responsible for anti-oxidant, anti-inflammatory, and anti-apoptotic effects. Therefore, researchers are interested in developing novel treatment options for neurological disorders. The emergence of unreported FGFs contributes to our understanding of their involvement in these conditions and encourages further exploration of innovative therapeutic approaches. All the data were obtained from published articles using PubMed, Web of Science, and Scopus databases using the search terms Fibroblast Growth Factor, PD, HD, AD, ALS, signalling pathways, and neurological disorders.

Pirfenidone in post-COVID-19 pulmonary fibrosis (FIBRO-COVID): a phase 2 randomised clinical trial

BACKGROUND

Patients with severe COVID-19 may develop lung fibrosis. Pirfenidone is an anti-fibrotic drug approved for idiopathic pulmonary fibrosis. The efficacy and safety of pirfenidone in patients with fibrotic interstitial lung changes after recovery from severe COVID-19 pneumonia were evaluated.

METHODS

This was a phase 2, double-blind, placebo-controlled, Spanish multicentre clinical trial. Patients were randomised to receive pirfenidone or placebo (2:1) for 24 weeks. The primary end-point was the proportion of patients that improved, considered when percentage change in forced vital capacity (FVC) was ≥10% and/or any reduction in the fibrotic score on chest high-resolution computed tomography (HRCT). Secondary end-points included health-related quality of life (HRQoL), exercise capacity and drug safety profile.

RESULTS

From 119 eligible patients, 113 were randomised and 103 were analysed (pirfenidone n=69 and placebo n=34). Most patients were male (73.5%) and were receiving low-dose prednisone; mean age was 63.7 years and mean body mass index was 29 kg·m-2. The percentage of patients that improved was similar in the pirfenidone and placebo groups (79.7% versus 82.3%, respectively). The mean predicted FVC increased by 12.74±20.6% with pirfenidone and 4.35±22.3% with placebo (p=0.071), and the HRCT (%) fibrotic score decreased by 5.44±3.69% with pirfenidone and 2.57±2.59% with placebo (p=0.52). Clinically meaningful improvement in HRQoL was not statistically different (55.2% in the pirfenidone group and 39.4% in the placebo group). Exercise capacity, adverse events and hospitalisations were similar between groups. No deaths were reported.

CONCLUSIONS

The overall improvements in lung function and HRCT fibrotic score after 6 months with pirfenidone were not significantly different than with placebo.

Decrypting the Possible Mechanistic Role of Fenofibrate in Alzheimer's Disease and Type 2 Diabetes: The Truth and Mystery

Alzheimer's disease (AD) is a neurodegenerative disease caused by the progressive deposition of extracellular amyloid beta (Aβ) and intracellular neurofibrillary tangles (NFTs). Of note, metabolic disorders such as insulin resistance (IR) and type 2 diabetes (T2D) are associated with the development of brain IR and associated neurodegeneration. In addition, AD neuropathology and linked cognitive impairment accelerate the development of peripheral IR and the progression of T2D. Therefore, there is a bidirectional relationship between T2D and AD. It has been demonstrated that AD and T2D induce dysregulation of peroxisome proliferator-activated receptor alpha (PPAR-α) leading to the central and peripheral metabolic disturbances. Hence, dysregulated PPAR-α could be a shared mechanism in both AD and T2D, and restoration of PPAR-α signalling by PPAR-α agonist fenofibrate (FN) may alleviate T2D and AD. Therefore, this review aims to shed light on the potential involvement of PPAR-α in T2D and AD, and how FN could be effective in the management of AD. FN seems to be effective in both AD and T2D by dual neuroprotective and antidiabetic effects that can mitigate AD neuropathology and T2D-related complications by modulating various cellular processes and inflammatory signalling pathways. In conclusion, FN could be a possible candidate in the management of AD and T2D by modulating different signalling pathways involved in the pathogenesis of these conditions.

The Role of Yes-Associated Protein in Inflammatory Diseases and Cancer

Yes-associated protein (YAP) plays a central role in the Hippo pathway, primarily governing cell proliferation, differentiation, and apoptosis. Its significance extends to tumorigenesis and inflammatory conditions, impacting disease initiation and progression. Given the increasing relevance of YAP in inflammatory disorders and cancer, this study aims to elucidate its pathological regulatory functions in these contexts. Specifically, we aim to investigate the involvement and molecular mechanisms of YAP in various inflammatory diseases and cancers. We particularly focus on how YAP activation, whether through Hippo-dependent or independent pathways, triggers the release of inflammation and inflammatory mediators in respiratory, cardiovascular, and digestive inflammatory conditions. In cancer, YAP not only promotes tumor cell proliferation and differentiation but also modulates the tumor immune microenvironment, thereby fostering tumor metastasis and progression. Additionally, we provide an overview of current YAP-targeted therapies. By emphasizing YAP's role in inflammatory diseases and cancer, this study aims to enhance our understanding of the protein's pivotal involvement in disease processes, elucidate the intricate pathological mechanisms of related diseases, and contribute to future drug development strategies targeting YAP.

The Novel Effect and Potential Mechanism of Lactoferrin on Organ Fibrosis Prevention

Organ fibrosis is gradually becoming a human health and safety problem, and various organs of the body are likely to develop fibrosis. The ultimate pathological feature of numerous chronic diseases is fibrosis, and few interventions are currently available to specifically target the pathogenesis of fibrosis. The medical detection of organ fibrosis has gradually matured. However, there is currently no effective treatment method for these diseases. Therefore, we need to strive for developing effective and reliable drugs or substances to treat and prevent fibrotic diseases. Lactoferrin (LF) is a multifunctional glycoprotein with many pathological and physiologically active effects, such as antioxidant, anti-inflammatory and antimicrobial effects, and it protects against pathological and physiological conditions in various disease models. This review summarizes the effects and underlying mechanisms of LF in preventing organ fibrosis. As a naturally active substance, LF can be used as a promising and effective drug for the prevention and remission of fibrotic diseases.

Tackling pulmonary fibrosis risks in post-COVID-19: cutting-edge treatments

INTRODUCTION

Pulmonary fibrosis (PF) post-COVID-19 has been identified as an important complication of Long-COVID, especially in patients with severe respiratory symptoms. High-resolution computed tomography (HRCT) is the main tool for detecting fibrotic lesions in patients with PF post-COVID-19.

AREAS COVERED

We conducted a systematic review with the following objectives: (1) to summarize the incidence and disease burden of post‑COVID‑19 pulmonary fibrosis, (2) to provide information on available therapies and drugs for its management, (3) to comprehensively evaluate the initial treatment efficacy of these drugs, and (4) to identify the limitations and challenges associated with current treatment approaches.

EXPERT OPINION

Cutting-edge treatments for PF post-COVID-19 are focused on the complex and multifactorial nature of the disease progreession during Long COVID, which involves chronic inflammation, fibroblast activation, and excessive extracellular matrix deposition leading to stiffening and fibrosis of lung tissue. While traditional antifibrotic drugs with nintedanid and pirfenidone are being used, novel therapies with anti-interleukines, mesenchymal stem cells, and Rho-kinase inhibitors promise the new treatment approaches for patients with PF post-COVID-19. Further research and clinical trials are needed to determine the most effective strategies for managing this complex condition, with the goal of improving patient outcomes and quality of life.

Activating Sig-1R inhibits microvascular permeability by reducing LRRK2 expression in lipopolysaccharide-induced acute lung injury

BACKGROUND

Endothelial cells are the first and most damaged target cells during acute lung injury (ALI). Endothelial dysfunction increases pulmonary microvascular permeability, subsequently leading to pulmonary oedema and organ dysfunction; however, clinical treatments against microvascular permeability show poor efficacy. Herein, we aimed to explore the role of the Sigma-1 receptor (Sig-1R) in pulmonary microvascular permeability by constructing ALI animal and cell models, and further investigated the specific mechanisms.

METHODS

The effects of Sig-1R on lung injury and endothelial barrier disruption were examined in lipopolysaccharide (LPS)-induced mice and human umbilical vein endothelial cells (HUVECs), respectively. Transcriptome sequencing was carried out to identify possible targets of Sig-1R, and the specific mechanisms of Sig-1R action were investigated using RNA interference and plasmid transfection.

RESULTS

Analysis of a Gene expression omnibus dataset suggested that Sig-1R plays a protective role against vascular hyperpermeability in ALI. Downregulation of Sig-1R expression and endothelial barrier disruption were both observed in mice and HUVECs upon LPS stimulation. Sig-1R agonists attenuated vascular hyperpermeability in vivo and in vitro, further improving ALI. Sig-1R activation downregulated Leucine-rich repeat kinase 2 (LRRK2) expression in mice and HUVECs. LRRK2 knockdown ameliorated endothelial barrier disruption in mice and HUVECs. Overexpression of LRRK2 reversed the protective effect of Sig-1R activation on LPS-induced endothelial hyperpermeability. Furthermore, Sig1r knockdown exacerbated LPS-induced microvascular hyperpermeability, which was rescued by inhibition of LRRK2.

CONCLUSIONS

Sig-1R activation exerts a protective effect against LPS-induced microvascular hyperpermeability by downregulating LRRK2 expression, which could lead to the development of novel therapeutic strategies for treating ALI.

Pharmacological effects of koumine on acute lung injury in septic mice: From in vivo experiments and network pharmacology studies

Acute lung injury (ALI) caused by sepsis is one of the most common critical diseases, which is difficult to treat and has a high fatality rate. Koumine is one of the main active components of Gelsemium plants and has been confirmed to have potential for drug development; however, its therapeutic effects on ALI have not yet been studied. This study established ALI due to sepsis using cecal ligation and puncture (CLP) and assessed the therapeutic effects of koumine by measuring mouse survival rates, lung tissue pathological damage, inflammatory factors, and oxidative stress levels. Additionally, network pharmacology was utilized to explore the underlying mechanisms. The results showed that koumine inhibited the release of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and interleukin-1β (IL-1β), thereby inhibiting inflammatory response, reducing lung injury score and lung wet to dry ratio. In addition, koumine reduced oxidative stress in mice by reducing myeloperoxidase (MPO) and malondialdehyde (MDA) and increasing superoxide dismutase (SOD) content. Network pharmacology analysis showed that 52 putative targets were relevant, and SLC6A4, HTR3A, JAK2 and JAK3 were the key targets. GO and KEGG pathway enrichment analysis showed that the related mechanisms involved neuroactive ligand-receptor interaction, calcium signaling pathway, serotonergic synapses, cholinergic synapses, etc. In summary, this study confirmed the potential therapeutic effect of koumine in sepsis induced ALI, suggesting its development prospect as a novel candidate drug for ALI, and providing data support.

Anti-Inflammatory Effects of Aptamin C in Pulmonary Fibrosis Induced by Bleomycin

Background/Objectives: Vitamin C is a well-known antioxidant with antiviral, anticancer, and anti-inflammatory properties. However, its therapeutic applications are limited by rapid oxidation due to heat and light sensitivity. Aptamin C, which employs aptamers to bind vitamin C, has demonstrated enhanced stability and efficacy. This study investigates the potential of Aptamin C to inhibit the progression of pulmonary fibrosis, a prominent inflammatory lung disease with no effective treatment. Methods: Mice bearing bleomycin-induced pulmonary fibrosis were administered vitamin C or Aptamin C, and their weight changes and survival rates were monitored. Inflammatory cell infiltration was assessed in the bronchoalveolar lavage fluid (BALF), and the degree of alveolar fibrosis was measured by H&E and Masson's trichrome staining. To elucidate the mechanism of action of Aptamin C, Western blot analysis was performed in HaCaT and lung tissues from bleomycin-induced pulmonary fibrosis mice. Results: The Aptamin C-treated group showed a notably higher survival rate at 50%, whereas all subjects in the vitamin C-treated group died. Histological examination of lung tissue showed that inflammation was significantly suppressed in the Aptamin C-supplemented group compared to the vitamin C-supplemented group, with a 10% greater reduction in cell infiltrations, along with noticeably less tissue damage. Additionally, it was observed that Aptamin C increased SVCT-1 expression in the HaCaT cells and the lung tissues. Conclusions: Taken together, Aptamin C not only increases the stability of vitamin C but also induces an increase in SVCT-1 expression, facilitating greater vitamin C absorption into cells and tissues, thereby inhibiting the progression of symptoms and associated inflammatory responses in pulmonary fibrosis.

Timing impact on the initiation of pirfenidone therapy on idiopathic pulmonary fibrosis disease progression

In this editorial, we comment on the article by Lei et al, with a specific focus on the timing of the initiation of the antifibrotic agent pirfenidone (PFD) in the management of idiopathic pulmonary fibrosis (IPF) and its impact on lung function of IPF patients. PFD is an antifibrotic agent that is widely used in the management of IPF in both early and advanced stages. It inhibits various pathways and has antifibrotic, anti-inflammatory, and antioxidant properties. Despite dosage lowering, PFD slowed IPF progression and maintained functional capacity. The 6-min walk distance test indicated that patients tolerated adverse events well, and PFD significantly reduced the incidence of progression episodes and death. Even when a single disease-progression event occurred, continuing PFD treatment had benefits.

Clinical usefulness of the serum levels of neuroinflammatory and lung fibrosis biomarkers in the assessment of cognitive dysfunction in post-COVID19 patients

A growing body of evidence indicates there is an increasing incidence of cognitive dysfunction in patients after coronavirus disease 2019 (COVID-19) infection. However, still lack diagnostic tools, which allow us to predict prognosis in such cases and improve the stratification of the disease. This study aims to evaluate the usefulness of the biomarkers that could allow to predict the severity and progression of COVID-19 in patients with post-COVID syndrome and cognitive problems. Data regarding clinical history, pre-existing conditions, chest CT scan, and therapy (remdesivir, steroids) were acquired. A total of 44 patients with hospitalized COVID-19, and healthy controls were enrolled in the investigation, and serum blood was obtained. After 6 months of observations, patients with COVID-19 were divided into two groups: first - without post-COVID syndrome and memory complaints, and second - with post-COVID and cognitive problems. Measurements of YKL-40 and MR-pro-ADM were taken in the serum with enzyme immunoassay kits at the time of admission (visit 1) and 6 months after discharge from the hospital (visit 2). Significantly higher concentrations of YKL-40 were found in patients with COVID-19 as compared to healthy individuals (p = 0.016). Moreover, YKL-40 ratio allowed to differentiate patients with and without post-COVID syndrome (median: 0.94 vs. 1.55, p = 0.004). Additionally, COVID-19 patients with dyspnea presented significantly elevated levels of MR-pro-ADM as compared to the group of COVID-19 survivors without dyspnea (p = 0.015). In the group of patients without post-COVID syndrome, the concentrations of YKL-40 and MR-pro-ADM decreased after treatment as compared to levels before therapy (77 vs. 36 ng/ml and 607 vs. 456 pmol/L). However, in patients with post-COVID syndrome and cognitive problems, the levels of both markers did not alter 6 months after hospital discharge in comparison to basal levels. Furthermore, after dexamethasone treatment the YKL-40 concentrations declined significantly (p = 0.003) in patients with COVID-19. This study demonstrated the predictive usefulness of YKL-40 as an indicator of successful treatment in patients with COVID-19 infection allowing risk stratification of hospitalized patients. It seems that indicators of neuroinflammation might have the potential to track development of cognitive complaints, however, it requires further investigations.

Use of pirfenidone in fibrotic interstitial lung diseases and beyond: a review

The pathophysiological mechanisms involved in fibrotic interstitial lung diseases (FILDs) are akin to those observed in idiopathic pulmonary fibrosis (IPF), implying the potential for shared therapeutic approaches. Pirfenidone exhibits antifibrotic and anti-inflammatory properties, making it the first small-molecule drug approved for treating IPF. Pirfenidone has been utilized in IPF treatment for more than one decade. However, guidelines for progressive pulmonary fibrosis (PPF) treatment suggest that further research and evidence are needed to fully comprehend its efficacy and safety across various PPF subtypes. In recent years, numerous studies have explored the use of pirfenidone in treating non-IPF FILD. Herein, we provide an overview of the latest research data on application of pirfenidone in occupational-related ILD, connective tissue disease-associated ILD, post-coronavirus disease-2019 pulmonary fibrosis, and other conditions. We summarize the level of evidence and highlight challenges associated with using pirfenidone in different FILDs to offer clinical guidance.

Synthetic Amphipathic Helical Peptide L-37pA Ameliorates the Development of Acute Respiratory Distress Syndrome (ARDS) and ARDS-Induced Pulmonary Fibrosis in Mice

In this study, we evaluated the ability of the synthetic amphipathic helical peptide (SAHP), L-37pA, which mediates pathogen recognition and innate immune responses, to treat acute respiratory distress syndrome (ARDS) accompanied by diffuse alveolar damage (DAD) and chronic pulmonary fibrosis (PF). For the modeling of ARDS/DAD, male ICR mice were used. Intrabronchial instillation (IB) of 200 µL of inflammatory agents was performed by an intravenous catheter 20 G into the left lung lobe only, leaving the right lobe unaffected. Intravenous injections (IVs) of L-37pA, dexamethasone (DEX) and physiological saline (saline) were used as therapies for ARDS/DAD. L37pA inhibited the circulating levels of inflammatory cytokines, such as IL-8, TNFα, IL1α, IL4, IL5, IL6, IL9 and IL10, by 75-95%. In all cases, the computed tomography (CT) data indicate that L-37pA reduced lung density faster to -335 ± 23 Hounsfield units (HU) on day 7 than with DEX and saline, to -105 ± 29 HU and -23 ± 11 HU, respectively. The results of functional tests showed that L-37pA treatment 6 h after ARDS/DAD initiation resulted in a more rapid improvement in the physiological respiratory lung by 30-45% functions compared with the comparison drugs. Our data suggest that synthetic amphipathic helical peptide L-37pA blocked a cytokine storm, inhibited acute and chronic pulmonary inflammation, prevented fibrosis development and improved physiological respiratory lung function in the ARDS/DAD mouse model. We concluded that a therapeutic strategy using SAHPs targeting SR-B receptors is a potential novel effective treatment for inflammation-induced ARDS, DAD and lung fibrosis of various etiologies.

Pirfenidone and Nintedanib in Pulmonary Fibrosis: Lights and Shadows

Pirfenidone and Nintedanib are specific drugs used against idiopathic pulmonary fibrosis (IPF) that showed efficacy in non-IPF fibrosing interstitial lung diseases (ILD). Both drugs have side effects that affect patients in different ways and have different levels of severity, making treatment even more challenging for patients and clinicians. The present review aims to assess the effectiveness and potential complications of Pirfenidone and Nintedanib treatment regimens across various ILD diseases. A detailed search was performed in relevant articles published between 2018 and 2023 listed in PubMed, UpToDate, Google Scholar, and ResearchGate, supplemented with manual research. The following keywords were searched in the databases in all possible combinations: Nintedanib; Pirfenidone, interstitial lung disease, and idiopathic pulmonary fibrosis. The most widely accepted method for evaluating the progression of ILD is through the decline in forced vital capacity (FVC), as determined by respiratory function tests. Specifically, a decrease in FVC over a 6-12-month period correlates directly with increased mortality rates. Antifibrotic drugs Pirfenidone and Nintedanib have been extensively validated; however, some patients reported several side effects, predominantly gastrointestinal symptoms (such as diarrhea, dyspepsia, and vomiting), as well as photosensitivity and skin rashes, particularly associated with Pirfenidone. In cases where the side effects are extremely severe and are more threatening than the disease itself, the treatment has to be discontinued. However, further research is needed to optimize the use of antifibrotic agents in patients with PF-ILDs, which could slow disease progression and decrease all-cause mortality. Finally, other studies are requested to establish the treatments that can stop ILD progression.

Strengthening pharmacotherapy research for COVID-19-induced pulmonary fibrosis

The global spread of severe acute respiratory syndrome coronavirus 2 has resulted in a significant number of individuals developing pulmonary fibrosis (PF), an irreversible lung injury. This condition can manifest within a short interval following the onset of pneumonia symptoms, sometimes even within a few days. While lung transplantation is a potentially lifesaving procedure, its limited availability, high costs, intricate surgeries, and risk of immunological rejection present significant drawbacks. The optimal timing of medication administration for coronavirus disease 2019 (COVID-19)-induced PF remains controversial. Despite this, it is crucial to explore pharmacotherapy interventions, involving early and preventative treatment as well as pharmacotherapy options for advanced-stage PF. Additionally, studies have demonstrated disparities in anti-fibrotic treatment based on race and gender factors. Genetic mutations may also impact therapeutic efficacy. Enhancing research efforts on pharmacotherapy interventions, while considering relevant pharmacological factors and optimizing the timing and dosage of medication administration, will lead to enhanced, personalized, and fair treatment for individuals impacted by COVID-19-related PF. These measures are crucial in lessening the burden of the disease on healthcare systems and improving patients' quality of life.

SARS-CoV-2 nucleocapsid protein promotes TMAO-induced NLRP3 inflammasome activation by SCAP-SREBP signaling pathway

The sterol regulatory element-binding protein (SREBP) activation and cytokine level were significantly increased in coronavirus disease-19. The NLRP3 inflammasome is an amplifier for cellular inflammation. This study aimed to elucidate the modulatory effect of SARS-CoV-2 nucleocapsid protein (SARS-CoV-2 NP) on trimethylamine N-oxide (TMAO)-induced lipogenesis and NLRP3 inflammasome activation and the underlying mechanisms in vascular smooth muscle cells (VSMCs). Our data indicated that SARS-CoV-2 NP activates the dissociation of the SREBP cleavage activating protein (SCAP) from the endoplasmic reticulum, resulting in SREBP activation, increased lipogenic gene expression, and NLRP3 inflammasome activation. TMAO was applied to VSMC-induced NLRP3 inflammasome by promoting the SCAP-SREBP complex endoplasmic reticulum-to-Golgi translocation, which facilitates directly binding of SARS-CoV-2 NP to the NLRP3 protein for NLRP3 inflammasome assembly. SARS-CoV-2 NP amplified the TMAO-induced lipogenic gene expression and NLRP3 inflammasome. Knockdown of SCAP-SREBP2 can effectively reduce lipogenic gene expression and alleviate NLRP3 inflammasome-mediated systemic inflammation in VSMCs stimulated with TMAO and SARS-CoV-2 NP. These results reveal that SARS-CoV-2 NP amplified TMAO-induced lipogenesis and NLRP3 inflammasome activation via priming the SCAP-SREBP signaling pathway.

Tofacitinib and pirfenidone as rescue therapies for severe COVID-19 in a patient with previously stable interstitial lung disease associated with Sjögren syndrome

Coronavirus disease 2019 (COVID-19) can lead to pulmonary fibrosis due to the inflammatory process in the lung, resulting in a series of respiratory consequences. Patients with underlying systemic diseases or pre-existing pulmonary diseases are particularly at risk of severe respiratory distress and persistent pulmonary abnormalities. Pirfenidone, a well-known anti-fibrotic agent recognized for its therapeutic effect on idiopathic pulmonary fibrosis, could be a feasible option in severe COVID-19 cases given the similar pathophysiological features shared with interstitial lung diseases. In this paper, we share our experience of early administration of pirfenidone in combination with tofacitinib in a 61-year-old female patient with severe COVID-19 pneumonia. Pirfenidone was initiated because of persistent dependence on high-flow oxygen support and even the requirement for mechanical ventilation due to disease progression after initial standard COVID-19 treatment. The patient was successfully extubated 15 days after the initiation of pirfenidone, and 13 days after extubation, she was completely weaned off supplemental oxygen. A series of chest radiographs and computed tomography scans demonstrated notable improvements in her lung condition. We propose a strategy of using pirfenidone plus tofacitinib as a rescue therapy in the management of patients with severe COVID-19.

COVID-19: A threat to the respiratory system

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), causes acute coronavirus disease-19 (COVID-19) that has emerged on a pandemic level. Coronaviruses are well-known to have a negative impact on the lungs and cardiovascular system. SARS-CoV-2 induces a cytokine storm that primarily targets the lungs, causing widespread clinical disorders, including COVID-19. Although, SARS-CoV-2 positive individuals often show no or mild upper respiratory tract symptoms, severe cases can progress to acute respiratory distress syndrome (ARDS). Novel CoV-2 infection in 2019 resulted in viral pneumonia as well as other complications and extrapulmonary manifestation. ARDS is also linked to a higher risk of death. Now, it is essential to develop our perception of the long term sequelae coronavirus infection for the identification of COVID-19 survivors who are at higher risk of developing the chronic lung fibrosis. This review study was planned to provide an overview of the effects of SARS-CoV-2 infection on various parts of the respiratory system such as airways, pulmonary vascular, lung parenchymal and respiratory neuromuscular system as well as the potential mechanism of the ARDS related respiratory complications including the lung fibrosis in patients with severe COVID-19.

Association Between COVID-19 Infection and Pulmonary Fibrosis: A Nested Case-Control Study

BACKGROUND

Pulmonary fibrosis is associated with significant morbidity. Data are scarce on the link between coronavirus disease (COVID-19) and pulmonary fibrosis. We aimed to assess the association between COVID-19 with pulmonary fibrosis.

METHODS

We conducted a nested case-control study in a cohort of 2,894,801 adults without a diagnosis of pulmonary fibrosis. The underlying cohort consisted of members of the largest healthcare provider in Israel aged 18 years or older as of May 1, 2020. Subjects were followed up from cohort entry until June 30, 2022, for the occurrence of pulmonary fibrosis. Ten randomly selected controls were matched to each case of pulmonary fibrosis on age, sex, and calendar time. To account for surveillance bias a lag time of 60 days was used for ascertainment of prior COVID-19 and COVID-19 severity.

RESULTS

During follow-up 1284 patients were newly diagnosed with pulmonary fibrosis and matched with 12,840 controls. Multivariable conditional logistic-regression models showed that the odds ratio for pulmonary fibrosis was 1.80 (95% confidence interval, 1.47-2.19) in patients with COVID-19 compared with no COVID-19. The multivariable odds ratio for pulmonary fibrosis was 1.33 (1.06-1.68), 2.98 (1.16-7.65), and 9.30 (5.77-14.98) for mild, moderate, and severe COVID-19, respectively, compared with no COVID-19. The magnitude of the association was attenuated but remained statistically significant for severe disease when the lag time was extended to 180 days (1.08 [0.78-1.49], 2.37 [0.75-7.46], and 5.34 [2.75-10.36] for mild, moderate, and severe COVID-19, respectively).

CONCLUSIONS

COVID-19 appears to be associated with an increased risk of pulmonary fibrosis and the magnitude of the association increases with COVID-19 severity.

Prolonged-release pirfenidone in patients with pulmonary fibrosis as a phenotype of post-acute sequelae of COVID-19 pneumonia. Safety and efficacy

INTRODUCTION

One of the major concerns with post-acute sequelae of COVID-19 (PASC) is the development of pulmonary fibrosis, for which no approved pharmacological treatment exists. Therefore, the primary aim of this open-label study was to evaluate the safety and the potential clinical efficacy of a prolonged-release pirfenidone formulation (PR-PFD) in patients having PASC-pulmonary fibrosis.

METHODS

Patients with PASC-pulmonary fibrosis received PR-PFD 1800 mg/day (1200 mg in the morning after breakfast and 600 mg in the evening after dinner) for three months. Blood samples were taken to confirm the pharmacokinetics of PR-PFD, and adverse events (AEs) were evaluated monthly using a short questionnaire. Symptoms, dyspnea, and pulmonary function tests (spirometry, diffusing capacity for carbon monoxide, plethysmography, and 6-min walk test [6MWT]) were evaluated at baseline, and one and three months after having started the PR-PFD treatment.

RESULTS

Seventy subjects with mild to moderate lung restriction were included. The most common AEs were diarrhea (23%), heartburn (23%), and headache (16%), for which no modifications in the drug study were needed. Two patients died within the first 30 days of enrolment, and three opted not to continue the study, events which were not associate with PR-PFD. Pulmonary function testing, 6MWT, dyspnea, symptoms, and CT scan significantly improved after three months of treatment with PR-PFD.

CONCLUSION

In patients with PASC pulmonary fibrosis, three months' treatment with PR-PFD was safe and showed therapeutic efficacy. Still, it remains to be seen whether the pulmonary fibrotic process remains stable, becomes progressive or will improve.

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.

Insights on Covid-19 with superimposed pulmonary histoplasmosis: The possible nexus

A novel coronavirus (CoV) known as severe acute respiratory syndrome CoV type 2 is the causative agent for the development of CoV disease 2019 (Covid-19). Covid-19 may increase the risk of developing pulmonary histoplasmosis due to immune dysregulation. In addition, Covid-19 may enhance the propagation of acute pulmonary histoplasmosis due to lung injury and inflammation, and using corticosteroids in severely affected Covid-19 patients may reactivate latent pulmonary histoplasmosis. Likewise, activation of inflammatory signaling pathways during H. capsulatum infection may increase the severity of Covid-19 and vice versa. Furthermore, lymphopenia in Covid-19 may increase the risk for the progress of pulmonary histoplasmosis besides activation of inflammatory signaling pathways during H. capsulatum infection may increase the severity of Covid-19 and vice versa. Therefore, this critical review aimed to find the potential link between Covid-19 pneumonia and pulmonary histoplasmosis concerning the immunological response.

Post-COVID-19 Pulmonary Fibrosis: Facts-Challenges and Futures: A Narrative Review

Patients with coronavirus disease 2019 (COVID-19) usually suffer from post-acute sequelae of coronavirus disease 2019 (PASC). Pulmonary fibrosis (PF) has the most significant long-term impact on patients' respiratory health, called post-COVID-19 pulmonary fibrosis (PC19-PF). PC19- PF can be caused by acute respiratory distress syndrome (ARDS) or pneumonia due to COVID-19. The risk factors of PC19-PF, such as older age, chronic comorbidities, the use of mechanical ventilation during the acute phase, and female sex, should be considered. Individuals with COVID-19 pneumonia symptoms lasting at least 12 weeks following diagnosis, including cough, dyspnea, exertional dyspnea, and poor saturation, accounted for nearly all disease occurrences. PC19-PF is characterized by persistent fibrotic tomographic sequelae associated with functional impairment throughout follow-up. Thus, clinical examination, radiology, pulmonary function tests, and pathological findings should be done to diagnose PC19-PF patients. PFT indicated persistent limitations in diffusion capacity and restrictive physiology, despite the absence of previous testing and inconsistency in the timeliness of assessments following acute illness. It has been hypothesized that PC19-PF patients may benefit from idiopathic pulmonary fibrosis treatment to prevent continued infection-related disorders, enhance the healing phase, and manage fibroproliferative processes. Immunomodulatory agents might reduce inflammation and the length of mechanical ventilation during the acute phase of COVID-19 infection, and the risk of the PC19-PF stage. Pulmonary rehabilitation, incorporating exercise training, physical education, and behavioral modifications, can improve the physical and psychological conditions of patients with PC19-PF.

Serum from Myalgic encephalomyelitis/chronic fatigue syndrome patients causes loss of coherence in cellular circadian rhythms

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a disabling disorder characterized by disrupted daily patterns of activity, sleep, and physiology. Past studies in ME/CFS patients have examined circadian rhythms, suggested that desynchronization between central and peripheral rhythms may be an important pathological feature, and identified associated changes in post-inflammatory cytokines such as transforming growth factor beta (TGFB). However, no previous studies have examined circadian rhythms in ME/CFS using cellular models or studied the role of cytokines on circadian rhythms. In this study, we used serum samples previously collected from ME/CFS patients (n = 20) selected for the presence of insomnia symptoms and matched controls (n = 20) to determine the effects of serum factors and TGFB on circadian rhythms in NIH3T3 mouse immortalized fibroblasts stably transfected with the Per2-luc bioluminescent circadian reporter. Compared to control serum, ME/CFS serum caused a significant loss of rhythm robustness (decreased goodness of fit) and nominally increased the rate of damping of cellular rhythms. Damping rate was associated with insomnia severity in ME/CFS patients using the Pittsburgh Sleep Quality Index (PSQI). Recombinant TGFB1 peptide applied to cells reduced rhythm amplitude, caused phase delay and decreased robustness of rhythms. However, there was no difference in TGFB1 levels between ME/CFS and control serum indicating the effects of serum on cellular rhythms cannot be explained by levels of this cytokine. Future studies will be required to identify additional serum factors in ME/CFS patients that alter circadian rhythms in cells.

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.

Inhibitory effect of lactoferrin-coated zinc nanoparticles on SARS-CoV-2 replication and entry along with improvement of lung fibrosis induced in adult male albino rats

Severe acute respiratory syndrome 2019-new coronavirus (SARS-CoV-2) is a major global challenge caused by a pandemic disease, named 'COVID-19' with no effective and selective therapy available so far. COVID-19-associated mortality is directly related to the inability to suppress the viral infection and the uncontrolled inflammatory response. So, we investigated the antiviral efficiency of the nanofabricated and well-characterized lactoferrin-coated zinc nanoparticles (Lf-Zn-NPs) on SARS-CoV-2 replication and entry into host cells. Lf-Zn-NPs showed potent inhibition of the entry of SARS-CoV-2 into the host cells by inhibition of ACE2, the SARS-CoV-2 receptor. This inhibitory activity of Lf-Zn-NPs to target the interaction between the SARS-CoV-2 spike protein and the ACE2 receptor offers potent protection against COVID-19 outbreaks. Moreover, the administration of Lf-Zn-NPs markedly improved lung fibrosis disorders, as supported by histopathological findings and monitored by the significant reduction in the values of CRP, LDH, ferritin, and D-dimer, with a remarkable rise in CD4+, lung SOD, GPx, GSH, and CAT levels. Lf-Zn-NPs revealed therapeutic efficiency against lung fibrosis owing to their anti-inflammatory, antioxidant, and ACE2-inhibiting activities. These findings suggest a promising nanomedicine agent against COVID-19 and its complications, with improved antiviral and immunomodulatory properties as well as a safer mode of action.

Ligustilide, a novel SIRT1 agonist, alleviates lipopolysaccharide-induced acute lung injury through deacetylation of NICD

Development and progression of sepsis-induced acute lung injury (ALI) involve apoptosis and oxidative stress in lung epithelial cells. Ligustilide (LIG) is one of the main bioactive constituents derived from the Angelica sinensis. As a novel SIRT1 agonist, LIG owns powerful anti-inflammatory and antioxidative properties, exerting remarkable therapeutic effects on cancers, neurological disorders, and diabetes mellitus. However, whether LIG could protect against lipopolysaccharide (LPS)-induced ALI by activating SIRT1 remains unclear. Mice underwent intratracheal LPS injection to mimic sepsis-induced ALI while MLE-12 cells were treated with LPS for 6 h to establish an in vitro ALI model. At the same time, mice or MLE-12 cells were treated with different doses of LIG to access its pharmacological effect. The results demonstrated that LIG pretreatment could improve LPS-induced pulmonary dysfunction and pathological injury, apart from increasing 7-day survival rate. In addition, LIG pretreatment also decreased inflammation, oxidative stress and apoptosis during LPS-induced ALI. Mechanically, LPS stimulation decreased the expression and activity of SIRT1 but increased the expression of Notch1 and NICD. And LIG could also enhance the interaction between SIRT1 and NICD, thus deacetylating NICD. In vitro experiments also unveiled that EX-527, a selective SIRT1 inhibitor, could abolish LIG-elicited protection in LPS-treated MLE-12 cells. And in SIRT1 knockout mice with ALI, LIG pretreatment also lost its effects on inflammation, apoptosis, and oxidative stress during ALI.

The Potential Nexus between Helminths and SARS-CoV-2 Infection: A Literature Review

Chronic helminth infections (CHIs) can induce immunological tolerance through the upregulation of regulatory T cells. In coronavirus disease 2019 (COVID-19), abnormal adaptive immune response and exaggerated immune response may cause immune-mediated tissue damage. Severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) and CHIs establish complicated immune interactions due to SARS-CoV-2-induced immunological stimulation and CHIs-induced immunological tolerance. However, COVID-19 severity in patients with CHIs is mild, as immune-suppressive anti-inflammatory cytokines counterbalance the risk of cytokine storm. Since CHIs have immunomodulatory effects, therefore, this narrative review aimed to clarify how CHIs modulate the immunoinflammatory response in SARS-CoV-2 infection. CHIs, through helminth-derived molecules, may suppress SARS-CoV-2 entry and associated hyperinflammation through attenuation of the inflammatory signaling pathway. In addition, CHIs may reduce the COVID-19 severity by reducing the SARS-CoV-2 entry points in the initial phase and immunomodulation in the late phase of the disease by suppressing the release of pro-inflammatory cytokines. In conclusion, CHIs may reduce the severity of SARS-CoV-2 infection by reducing hyperinflammation and exaggerated immune response. Thus, retrospective and prospective studies are recommended in this regard.

Pharmacological approaches to pulmonary fibrosis following COVID-19

Background: In the past few years, COVID-19 became the leading cause of morbidity and mortality worldwide. Although the World Health Organization has declared an end to COVID-19 as a public health emergency, it can be expected, that the emerging new cases at the top of previous ones will result in an increasing number of patients with post-COVID-19 sequelae. Despite the fact that the majority of patients recover, severe acute lung tissue injury can in susceptible individuals progress to interstitial pulmonary involvement. Our goal is to provide an overview of various aspects associated with the Post-COVID-19 pulmonary fibrosis with a focus on its potential pharmacological treatment options. Areas covered: We discuss epidemiology, underlying pathobiological mechanisms, and possible risk and predictive factors that were found to be associated with the development of fibrotic lung tissue remodelling. Several pharmacotherapeutic approaches are currently being applied and include anti-fibrotic drugs, prolonged use or pulses of systemic corticosteroids and non-steroidal anti-inflammatory and immunosuppressive drugs. In addition, several repurposed or novel compounds are being investigated. Fortunately, clinical trials focused on pharmacological treatment regimens for post-COVID-19 pulmonary fibrosis have been either designed, completed or are already in progress. However, the results are contrasting so far. High quality randomised clinical trials are urgently needed with respect to the heterogeneity of disease behaviour, patient characteristics and treatable traits. Conclusion: The Post-COVID-19 pulmonary fibrosis contributes to the burden of chronic respiratory consequences among survivors. Currently available pharmacotherapeutic approaches mostly comprise repurposed drugs with a proven efficacy and safety profile, namely, corticosteroids, immunosuppressants and antifibrotics. The role of nintedanib and pirfenidone is promising in this area. However, we still need to verify conditions under which the potential to prevent, slow or stop progression of lung damage will be fulfilled.

Thalidomide interaction with inflammation in idiopathic pulmonary fibrosis

The "Thalidomide tragedy" is a landmark in the history of the pharmaceutical industry. Despite limited clinical trials, there is a continuous effort to investigate thalidomide as a drug for cancer and inflammatory diseases such as rheumatoid arthritis, lepromatous leprosy, and COVID-19. This review focuses on the possibilities of targeting inflammation by repurposing thalidomide for the treatment of idiopathic pulmonary fibrosis (IPF). Articles were searched from the Scopus database, sorted, and selected articles were reviewed. The content includes the proven mechanisms of action of thalidomide relevant to IPF. Inflammation, oxidative stress, and epigenetic mechanisms are major pathogenic factors in IPF. Transforming growth factor-β (TGF-β) is the major biomarker of IPF. Thalidomide is an effective anti-inflammatory drug in inhibiting TGF-β, interleukins (IL-6 and IL-1β), and tumour necrosis factor-α (TNF-α). Thalidomide binds cereblon, a process that is involved in the proposed mechanism in specific cancers such as breast cancer, colon cancer, multiple myeloma, and lung cancer. Cereblon is involved in activating AMP-activated protein kinase (AMPK)-TGF-β/Smad signalling, thereby attenuating fibrosis. The past few years have witnessed an improvement in the identification of biomarkers and diagnostic technologies in respiratory diseases, partly because of the COVID-19 pandemic. Hence, investment in clinical trials with a systematic plan can help repurpose thalidomide for pulmonary fibrosis.

Pulmonary fibrosis: A short- or long-term sequelae of severe COVID-19?

The pandemic of coronavirus disease 2019 (COVID‑19), caused by a novel severe acute respiratory syndrome (SARS) coronavirus 2 (SARS-CoV-2), has caused an enormous impact on the global healthcare. SARS-CoV-2 infection primarily targets the respiratory system. Although most individuals testing positive for SARS-CoV-2 present mild or no upper respiratory tract symptoms, patients with severe COVID-19 can rapidly progress to acute respiratory distress syndrome (ARDS). ARDS-related pulmonary fibrosis is a recognized sequelae of COVID-19. Whether post-COVID-19 lung fibrosis is resolvable, persistent, or even becomes progressive as seen in human idiopathic pulmonary fibrosis (IPF) is currently not known and remains a matter of debate. With the emergence of effective vaccines and treatments against COVID-19, it is now important to build our understanding of the long-term sequela of SARS-CoV-2 infection, to identify COVID-19 survivors who are at risk of developing chronic pulmonary fibrosis, and to develop effective anti-fibrotic therapies. The current review aims to summarize the pathogenesis of COVID-19 in the respiratory system and highlights ARDS-related lung fibrosis in severe COVID-19 and the potential mechanisms. It envisions the long-term fibrotic lung complication in COVID-19 survivors, in particular in the aged population. The early identification of patients at risk of developing chronic lung fibrosis and the development of anti-fibrotic therapies are discussed.

Possibilities of non-invasive diagnosis of fibrotic phenotype of interstitial lung diseases

Progressive pulmonary fibrosis is a major problem in respiratory medicine. Currently, there are no reliable biomarkers for early diagnosis of progressive pulmonary fibrosis, which leads to delayed diagnosis.

AIM

To determine the role of serum biomarkers CA-19-9 and CA-125 and the possibilities of capillaroscopy of the nail fold in the diagnosis of progressive pulmonary fibrosis.

MATERIALS AND METHODS

The study included 43 patients with interstitial changes in the lungs. Based on the presence/absence of signs of progression over the previous 12 months, patients were divided into 2 groups. All patients underwent forced spirometry, body plethysmography, diffusion test, CT, lung ultrasound, capillaroscopy of the nail fold, study of serum concentrations of CA-19-9 and CA-125.

RESULTS

In the group of patients with a progressive fibrotic phenotype of Interstitial lung diseases, a greater severity of capillaroscopic changes and a higher level of CA-19-9 were revealed. Correlation of these parameters with changes according to CT scan data (Warrick test) and lung ultrasound was shown.

CONCLUSION

The data obtained demonstrate the possibilities of non-invasive diagnosis of progressive fibrosing interstitial lung diseases and require further research and prospective follow-up to assess the diagnostic and prognostic role of the studied biomarkers, as well as to determine their place in clinical practice.

Higher proinflammatory responses possibly contributing to suppressed cytotoxicity in patients with COVID-19 associated mucormycosis

INTRODUCTION

COVID-19 Associated Mucormycosis (CAM), an opportunistic fungal infection, surged during the second wave of SARS Cov-2 pandemic. Since immune responses play an important role in controlling this infection in immunocompetent hosts, it is required to understand immune perturbations associated with this condition for devising immunotherapeutic strategies for its control. We conducted a study to determine different immune parameters altered in CAM cases as compared to COVID-19 patients without CAM.

METHODOLOGY

Cytokine levels in serum samples of CAM cases (n = 29) and COVID-19 patients without CAM (n = 20) were determined using luminex assay. Flow cytometric assays were carried out in 20 CAM cases and 10 controls for determination of frequency of NK cells, DCs, phagocytes, T cells and their functionalities. The cytokine levels were analyzed for their association with each other as well as with T cell functionality. The immune parameters were also analyzed with respect to the known risk factors such as diabetes mellitus and steroid treatment.

RESULTS

Significant reduction in frequencies of total and CD56 + CD16 + NK cells (cytotoxic subset) was noted in CAM cases. Degranulation responses indicative of cytotoxicity of T cell were significantly hampered in CAM cases as compared to the controls. Conversely, phagocytic functions showed no difference in CAM cases versus their controls except for migratory potential which was found to be enhanced in CAM cases. Levels of proinflammatory cytokines such as IFN-γ, IL-2, TNF-α, IL-17, IL-1β, IL-18 and MCP-1 were significantly elevated in cases as compared to the control with IFN-γ and IL-18 levels correlating negatively with CD4 T cell cytotoxicity. Steroid administration was associated with higher frequency of CD56 + CD16- NK cells (cytokine producing subset) and higher MCP-1 levels. Whereas diabetic participants had higher phagocytic and chemotactic potential and had higher levels of IL-6, IL-17 and MCP-1.

CONCLUSION

CAM cases differed from the controls in terms of higher titers of proinflammatory cytokines, reduced frequency of total and cytotoxic CD56 + CD16 + NK cell. They also had reduced T cell cytotoxicity correlating inversely with IFN-γ and IL-18 levels, possibly indicating induction of negative feedback mechanisms while diabetes mellitus or steroid administration did not affect the responses negatively.

The potential role of scavenger receptor B type I (SR-BI) in SARS-CoV-2 infection

Scavenger receptor type B I (SR-BI), the major receptor for high-density lipoprotein (HDL) mediates the delivery of cholesterol ester and cholesterol from HDL to the cell membrane. SR-BI is implicated as a receptor for entry of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2). SR-BI is colocalized with the angiotensin-converting enzyme 2 (ACE2) increasing the binding and affinity of SARS-CoV-2 to ACE2 with subsequent viral internalization. SR-BI regulates lymphocyte proliferation and the release of pro-inflammatory cytokines from activated macrophages and lymphocytes. SR-BI is reduced during COVID-19 due to consumption by SARS-CoV-2 infection. COVID-19-associated inflammatory changes and high angiotensin II (AngII) might be possible causes of repression of SR-BI in SARS-CoV-2 infection. In conclusion, the downregulation of SR-BI in COVID-19 could be due to direct invasion by SARS-CoV-2 or through upregulation of pro-inflammatory cytokines, inflammatory signaling pathways, and high circulating AngII. Reduction of SR-BI in COVID-19 look like ACE2 may provoke COVID-19 severity through exaggeration of the immune response. Further studies are invoked to clarify the potential role of SR-BI in the pathogenesis of COVID-19 that could be protective rather than detrimental.

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.

Liposomal Forms of Fluoroquinolones and Antifibrotics Decorated with Mannosylated Chitosan for Inhalation Drug Delivery

The severe course of COVID-19 leads to the long-terming pulmonary diseases, such as bacterial pneumonia and post-COVID-19 pulmonary fibrosis. Thus, the essential task of biomedicine is a design of new effective drug formulations, including those for inhalation administration. In this work, we propose an approach to the creation of lipid–polymer delivery systems for fluoroquinolones and pirfenidone based on liposomes of various compositions decorated with mucoadhesive mannosylated chitosan. A generalizing study on the physicochemical patterns of the interactions of drugs with bilayers of various compositions was carried out, and the main binding sites were identified. The role of the polymer shell in the stabilization of vesicles and the delayed release of the contents has been demonstrated. For the liquid–polymer formulation of moxifloxacin, a prolonged accumulation of the drug in lung tissues was found after a single endotracheal administration to mice, significantly exceeding the control intravenous and endotracheal administration of the drug.

Ovatodiolide inhibits SARS-CoV-2 replication and ameliorates pulmonary fibrosis through suppression of the TGF-β/TβRs signaling pathway

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection continues to pose threats to public health. The clinical manifestations of lung pathology in COVID-19 patients include sustained inflammation and pulmonary fibrosis. The macrocyclic diterpenoid ovatodiolide (OVA) has been reported to have anti-inflammatory, anti-cancer, anti-allergic, and analgesic activities. Here, we investigated the pharmacological mechanism of OVA in suppressing SARS-CoV-2 infection and pulmonary fibrosis in vitro and in vivo. Our results revealed that OVA was an effective SARS-CoV-2 3CLpro inhibitor and showed remarkable inhibitory activity against SARS-CoV-2 infection. On the other hand, OVA ameliorated pulmonary fibrosis in bleomycin (BLM)-induced mice, reducing inflammatory cell infiltration and collagen deposition in the lung. OVA decreased the levels of pulmonary hydroxyproline and myeloperoxidase, as well as lung and serum TNF-ɑ, IL-1β, IL-6, and TGF-β in BLM-induced pulmonary fibrotic mice. Meanwhile, OVA reduced the migration and fibroblast-to-myofibroblast conversion of TGF-β1-induced fibrotic human lung fibroblasts. Consistently, OVA downregulated TGF-β/TβRs signaling. In computational analysis, OVA resembles the chemical structures of the kinase inhibitors TβRI and TβRII and was shown to interact with the key pharmacophores and putative ATP-binding domains of TβRI and TβRII, showing the potential of OVA as an inhibitor of TβRI and TβRII kinase. In conclusion, the dual function of OVA highlights its potential for not only fighting SARS-CoV-2 infection but also managing injury-induced pulmonary fibrosis.

A Potential Link Between Visceral Obesity and Risk of Alzheimer's Disease

Alzheimer's disease (AD) is the most common type of dementia characterized by the deposition of amyloid beta (Aβ) plaques and tau-neurofibrillary tangles in the brain. Visceral obesity (VO) is usually associated with low-grade inflammation due to higher expression of pro-inflammatory cytokines by adipose tissue. The objective of the present review was to evaluate the potential link between VO and the development of AD. Tissue hypoxia in obesity promotes tissue injury, production of adipocytokines, and release of pro-inflammatory cytokines leading to an oxidative-inflammatory loop with induction of insulin resistance. Importantly, brain insulin signaling is involved in the pathogenesis of AD and lower cognitive function. Obesity and enlargement of visceral adipose tissue are associated with the deposition of Aβ. All of this is consonant with VO increasing the risk of AD through the dysregulation of adipocytokines which affect the development of AD. The activated nuclear factor kappa B (NF-κB) pathway in VO might be a potential link in the development of AD. Likewise, the higher concentration of advanced glycation end-products in VO could be implicated in the pathogenesis of AD. Taken together, different inflammatory signaling pathways are activated in VO that all have a negative impact on the cognitive function and progression of AD except hypoxia-inducible factor 1 which has beneficial and neuroprotective effects in mitigating the progression of AD. In addition, VO-mediated hypoadiponectinemia and leptin resistance may promote the progression of Aβ formation and tau phosphorylation with the development of AD. In conclusion, VO-induced AD is mainly mediated through the induction of oxidative stress, inflammatory changes, leptin resistance, and hypoadiponectinemia that collectively trigger Aβ formation and neuroinflammation. Thus, early recognition of VO by visceral adiposity index with appropriate management could be a preventive measure against the development of AD in patients with VO.

The potential role of SARS-CoV-2 infection in acute coronary syndrome and type 2 myocardial infarction (T2MI): Intertwining spread

Coronavirus disease 2019 (COVID-19) is a novel pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It has been shown that SARS-CoV-2 infection-induced inflammatory and oxidative stress and associated endothelial dysfunction may lead to the development of acute coronary syndrome (ACS). Therefore, this review aimed to ascertain the link between severe SARS-CoV-2 infection and ACS. ACS is a spectrum of acute myocardial ischemia due to a sudden decrease in coronary blood flow, ranging from unstable angina to myocardial infarction (MI). Primary or type 1 MI (T1MI) is mainly caused by coronary plaque rupture and/or erosion with subsequent occlusive thrombosis. Secondary or type 2 MI (T2MI) is due to cardiac and systemic disorders without acute coronary atherothrombotic disruption. Acute SARS-CoV-2 infection is linked with the development of nonobstructive coronary disorders such as coronary vasospasm, dilated cardiomyopathy, myocardial fibrosis, and myocarditis. Furthermore, SARS-CoV-2 infection is associated with systemic inflammation that might affect coronary atherosclerotic plaque stability through augmentation of cardiac preload and afterload. Nevertheless, major coronary vessels with atherosclerotic plaques develop minor inflammation during COVID-19 since coronary arteries are not initially and primarily targeted by SARS-CoV-2 due to low expression of angiotensin-converting enzyme 2 in coronary vessels. In conclusion, SARS-CoV-2 infection through hypercytokinemia, direct cardiomyocyte injury, and dysregulation of the renin-angiotensin system may aggravate underlying ACS or cause new-onset T2MI. As well, arrhythmias induced by anti-COVID-19 medications could worsen underlying ACS.

Irisin attenuates fine particulate matter induced acute lung injury by regulating Nod2/NF-κB signaling pathway

Air pollution consisting of fine particulate matter (PM2.5) can induce or aggravate pulmonary inflammatory injury. Irisin has been shown to inhibit inflammation and help to protect against acute kidney, lung or brain injury. However, the role of irisin in lung inflammation after exposure to PM2.5 remains unclear. The aim of this study was to investigate the effect and molecular mechanism of irisin supplementation on in vitro and in vivo models of PM2.5-induced acute lung injury（ALI). C57BL/6 mice and alveolar macrophage cell line (MH-S) were treated with PM2.5. Histopathological examination and FNDC5/ irisin immunofluorescence staining was performed on lung tissue sections. MH-S cell viability was determined by CCK-8 assay. The levels of Nod2, NF-κB p65 and NLRP3 were detected by qRT-PCR and western blotting. The levels of cytokines (IL-1β, IL-18 and TNF-α) were detected by ELISA. PM2.5 exposure induced increased secretion of pro-inflammatory factors and activation of Nod2, NF-κB p65 and NLRP3 as well as endogenous levels of irisin. In vivo and in vitro inflammation was alleviated by irisin supplementation. Irisin significantly decreased IL-1β, IL-18, and TNF-α production at both mRNA and protein level. Expression levels of Nod2, NF-κB p65, and NLRP3 were all significantly affected by irisin. In vivo the degree of pulmonary injury and inflammatory infiltration was weakened after irisin administration. In vitro, irisin could inhibit the activation of the NLRP3 inflammasome for a sustained period of 24 h, and its inhibitory ability was gradually enhanced. In conclusion, our findings indicate that irisin can modulate the inflammatory injury of lung tissue caused by PM2.5 through the Nod2/NF-κB signaling pathway, suggesting that irisin can be a candidate for the therapeutic or preventive intervention in acute lung inflammation.

Dantrolene and ryanodine receptors in COVID-19: The daunting task and neglected warden

Dantrolene (DTN) is a ryanodine receptor (RyR) antagonist that inhibits Ca²⁺ release from stores in the sarcoplasmic reticulum. DTN is mainly used in the management of malignant hyperthermia. RyRs are highly expressed in immune cells and are involved in different viral infections, including severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), because Ca²⁺ is necessary for viral replication, maturation and release. DTN can inhibit the proliferation of SARS-CoV-2, indicating its potential role in reducing entry and pathogenesis of SARS-CoV-2. DTN may increase clearance of SARS-CoV-2 and promote coronavirus disease 2019 (COVID-19) recovery by shortening the period of infection. DTN inhibits N-methyl-D-aspartate (NMDA) mediated platelets aggregations and thrombosis. Therefore, DTN may inhibit thrombosis and coagulopathy in COVID-19 through suppression of platelet NMDA receptors. Moreover, DTN has a neuroprotective effect against SARS-CoV-2 infection-induced brain injury through modulation of NMDA receptors, which are involved in excitotoxicity, neuronal injury and the development of neuropsychiatric disorders. In conclusion, DTN by inhibiting RyRs may attenuate inflammatory disorders in SARS-CoV-2 infection and associated cardio-pulmonary complications. Therefore, DNT could be a promising drug therapy against COVID-19. Preclinical and clinical studies are warranted in this regards.

Targeting of neuroinflammation by glibenclamide in Covid-19: old weapon from arsenal

In coronavirus disease 2019 (Covid-19) era, neuroinflammation may develop due to neuronal tropism of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) and/or associated immune activation, cytokine storm, and psychological stress. SARS-CoV-2 infection and linked cytokine storm may cause blood-brain barrier (BBB) injury through which activated immune cells and SARS-CoV-2 can pass into the brain causing activation of glial cells with subsequent neuroinflammation. Different therapeutic regimens were suggested to alleviate Covid-19-induced neuroinflammation. Since glibenclamide has anti-inflammatory and neuroprotective effects, it could be effective in mitigation of SARS-CoV-2 infection-induced neuroinflammation. Glibenclamide is a second-generation drug from the sulfonylurea family, which acts by inhibiting the adenosine triphosphate (ATP)-sensitive K channel in the regulatory subunit of type 1 sulfonylurea receptor (SUR-1) in pancreatic β cells. Glibenclamide reduces neuroinflammation and associated BBB injury by inhibiting the nod-like receptor pyrin 3 (NLRP3) inflammasome, oxidative stress, and microglial activation. Therefore, glibenclamide through inhibition of NLRP3 inflammasome, microglial activation, and oxidative stress may attenuate SARS-CoV-2-mediated neuroinflammation.

Statins Use in Alzheimer Disease: Bane or Boon from Frantic Search and Narrative Review

Alzheimer’s disease (AD) was used to describe pre-senile dementia to differentiate it from senile dementia, which develops in the adult age group of more than 65 years. AD is characterized by the deposition of amyloid beta (Aβ) plaque and tau-neurofibrillary tangles (TNTs) in the brain. The neuropathological changes in AD are related to the deposition of amyloid plaques, neurofibrillary tangles, and progression of neuroinflammation, neuronal mitochondrial dysfunction, autophagy dysfunction, and cholinergic synaptic dysfunction. Statins are one of the main cornerstone drugs for the management of cardiovascular disorders regardless of dyslipidemia status. Increasing the use of statins, mainly in the elderly groups for primary and secondary prevention of cardiovascular diseases, may affect their cognitive functions. Extensive and prolonged use of statins may affect cognitive functions in healthy subjects and dementia patients. Statins-induced cognitive impairments in both patients and health providers had been reported according to the post-marketing survey. This survey depends mainly on sporadic cases, and no cognitive measures were used. Evidence from prospective and observational studies gives no robust conclusion regarding the beneficial or detrimental effects of statins on cognitive functions in AD patients. Therefore, this study is a narrative review aimed with evidences to the beneficial, detrimental, and neutral effects of statins on AD.

Montelukast and Acute Coronary Syndrome: The Endowed Drug

Acute coronary syndrome (ACS) is a set of signs and symptoms caused by a reduction of coronary blood flow with subsequent myocardial ischemia. ACS is associated with activation of the leukotriene (LT) pathway with subsequent releases of various LTs, including LTB4, LTC4, and LTD4, which cause inflammatory changes and induction of immunothrombosis. LTs through cysteine leukotriene (CysLT) induce activation of platelets and clotting factors with succeeding coronary thrombosis. CysLT receptor (CysLTR) antagonists such as montelukast (MK) may reduce the risk of the development of ACS and associated complications through suppression of the activation of platelet and clotting factors. Thus, this critical review aimed to elucidate the possible protective role of MK in the management of ACS. The LT pathway is implicated in the pathogenesis of atherosclerosis, cardiac hypertrophy, and heart failure. Inhibition of the LT pathway and CysL1TR by MK might be effective in preventing cardiovascular complications. MK could be an effective novel therapy in the management of ACS through inhibition of pro-inflammatory CysLT1R and modulation of inflammatory signaling pathways. MK can attenuate thrombotic events by inhibiting platelet activation and clotting factors that are activated during the development of ACS. In conclusion, MK could be an effective agent in reducing the severity of ACS and associated complications. Experimental, preclinical, and clinical studies are recommended to confirm the potential therapeutic of MK in the management of ACS.