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JOURNAL OF CLINICAL MEDICINE OF KAZAKHSTAN
(E-ISSN 2313-1519)
Original Article
DOI: https://doi.org/10.23950/jcmk/13142
Role of pyroptosis in COVID-19
Mehmet ^elik1, Mehmet Re§at Ceylan1, Mahmut Alp Karahan2, Ismail Koyuncu3, Nevin Güler Dinner4, Sevil Alkan5
'Department of Infectious Diseases and Clinical Microbiology, Faculty of Medicine, University of Harran, §anliurfa, Turkey department of Anesthesiology, §Anliurfa Mehmet Akif iNAN Training and Research Hospital, §Anliurfa, Turkey Department of Medical Biochemistry, Faculty of Medicine, University of Harran, §anliurfa, Turkey Department of Statistics, Faculty of Science, University of Mugla Sitki Kogman, Mugla, Turkey 5Department of Infectious Diseases, Faculty of Medicine, Canakkale Onsekiz Mart University, Canakkale, Turkey
Received: 2023-01-27. Accepted: 2023-03-07
© ©
This work is licensed under a Creative Commons Attribution 4.0 International License
J Clin Med Kaz 2023; 20(2):39-45
Corresponding author: Mehmet £elik.
E-mail: dr.mcelik12@gmail.com; ORCID: 0000-0002-0583-929X
Abstract
Objectives: In this study, it was investigated the relationship between of gasdermin-D, caspase-1, IL-1 p and NLRP3, which are biomarkers that play an important role in the pyroptosis and COVID-19.
Material and methods: This study was carried out with 58 participants, 28 (48.28%) of whom were diagnosis of COVID-19, and 30 (51.72%) of whom were healthy volunteers (control group).
Results: There were no statistically significant differences between the gasdermin-D, caspase-1, IL-1p and NLRP3 levels as a result of all statistical comparisons performed. However, IL-1p values both at the discharge period and at hospitalization period were considerably higher than those of control group. At discharge period, IL-1p values of the patients with severe COVID-19 category had higher than moderate patients, and the patients with moderate than the patients with the mild patients.
Conclusion: It was observed that IL-1 p, which is one of the cytokines released as a result of cell death in the pyroptosis mechanism, was higher in the COVID-19 patients both the hospitalization and discharge periods compared to the control group. Although not statistically significant these results could support the relationship between the pyroptosis and COVID-19.
Key words: COVID-19, interleukin-1p, pyroptosis
Introduction
Coronaviruses are enveloped RNA viruses belonging to the beta-coronavirus genus in the Coronaviridae family [1]. After the pneumonia clustering detected on 31 December 2019 was determined to be caused by a new Coronavirus never before seen in humans, this Coronavirus was defined as SARS-CoV-2 [2]. SARS-CoV-2 has been described as the 7th Coronavirus, that is pathogenic in humans [1]. Coronavirus disease 2019 (COVID-19) was declared a pandemic by the World Health Organization (WHO) on March 11, 2020 [3]. The disease has spread to more than 220 countries the worldwide. The number of cases reached 515 million and deaths reached 6,254,140 worldwide [4].
While the disease may progress asymptomatically, it can also be seen in respiratory failure requiring mechanical ventilation, sepsis, septic shock and multiple organ failure [5]. COVID-19 is characterized by an abnormal host immune response, manifested by high blood cytokine, chemokine, and C-reactive protein (CRP) levels [6]. And it has been shown in many previous studies that COVID-19 can have multi-system involvement (cardiac, gastrointestinal, etc.) [7-14].
In addition to known cell death mechanisms such as necrosis, autophagy and apoptosis, a new type of cell death, the pyroptosis, has been defined in recent years. Pyroptosis is a type of programmed and inflammatory necrosis that occurs due to caspase (cysteinyl aspartate specific proteinase) activation and pore formation in the cell membrane conducted by the gasdermin protein
family. Pyroptosis results lytic cell death accompanied by the release of various inflammatory factors by inducing amplification of the cascade and of the inflammatory response. In addition, it is an important immune defense mechanism in the body that resists the invasion of external pathogens and plays a role in perceiving internal pathogenic signals in cells [15]. Various evidences have been shown to support that in severe COVID-19 cases, there are inflammasome activation, the pyroptosis and their critical roles. It was found that the pyroptosis is associated with caspase-1 activation, gasdermin-D (GSDMD) cleavage and increased levels of proinflammatory cytokines in primary monocytes and macrophages of COVID-19 patients [16-18]. In this study, it was investigated the relationship between of GSDMD, caspase-1, Interleukin-1p (IL-1p) and NOD-like receptor family pyrin domain-containing 3 (NLRP3), which are biomarkers that play an important role in the pyroptosis and COVID-19.
Material and methods
Study population and participant groups
The patients over 18 years of age, who were diagnosed with COVID-19 as a result of clinical signs, symptoms and laboratory tests and who were hospitalized at the COVID-19 ward of Harran University Medical Faculty Hospital and the control group consisting of healthy volunteers without any symptoms or underlying disease included in the study. The patient group consisted of the participants were diagnosed with a positive realtime reverse transcription-polymerase chain reaction (rRT-PCR) in addition to various symptoms and findings and were followed up in the hospital. The patients were grouped grounded on the "COVID 19 (2019-nCoV Disease) Guidelines" published by the Turkish Ministry of Health. According to this guideline, patients diagnosed with COVID-19 were divided into four subgroups; Group 1 was classified as mildly symptomatic, Group 2 as symptomatic (radiological involvement in addition to fever and respiratory symptoms), Group 3 as symptomatic (dyspnea, oxygen saturation <93% at rest) and Group 4 as critically ill (respiratory failure, clinical shock or organ failure requiring mechanical ventilation) [19].
Biochemical analyses
Blood samples were collected from both COVID-19 patients and healthy volunteers. Serum samples were obtained by centrifugation of the blood samples taken at 3500 rpm for 10 minutes and these serum samples were stored in the refrigerator at -80°C until the day of the study. GSDMD (Gasdermin D Elisa Kit (BT Lab Catalog no: E6838Hu)), caspase-1 (BT Lab; E2248Hu), IL-ip (Interleukin 1 Beta; BT Lab E0143Hu) and NLRP3 (Human Nlr Family Pyrin Domain, BT Lab E3886Hu)) levels were performed according to the commercially purchased ELISA kit protocol. After adding 100 ^l of a serum sample to the 96 plates in the kit, it was incubated at 37° C for 90 minutes. After incubation, the plate was emptied, washed twice with a washing solution, and dried. 100 ^l Biotin-labeled antibody was added and incubated at 37°C for one hour. After incubation, the plate was drained and washed three times with a washing solution and dried. 100 ^l HRP-Streptavidin Conjugate was added and incubated at 37°C for 30 minutes. After incubation, the plate was drained and washed five times with wash solution and dried. Then 90 ^l TMB Substrate was added and incubated at 37°C in the dark. 50^l of Stop Solution was added after color formation was observed. Data were obtained by reading the plates in a microplate reader (Biotek-Cytation-1) at 450 nm absorbance.
Statistical analyses
SPSS version 22.0 was employed in the statistical analysis (SPSS Inc., Chicago, IL). G*Power v3.1.9.4 was implemented to conduct a power analysis in order to determine the sample size. There were four ways to sum up descriptive statistics: number, percentage, mean, and standard deviation (S.D). Continuous variables were examined to see if they adhered to the normal distribution using the Kolmogorov-Smirnov test. With the help of the paired samples t-test and the two independent sample t-test, continuous variables with the normal distribution were examined. The variables that did not exhibit a normal distribution were subjected to the Mann-Whitney U test and the Wilcoxon sign test. For comparing more than two continuous variables, use the Kruskal-Wallis test. For all statistical tests, p 0.05 was accepted as the significance level.
Results
A total of 58 participants, including 28 (48.28%) COVID-19 patients hospitalized in the COVID-19 ward and 30 (51.72%) healthy controls, were included in the current study.
15 (53.6%) of the patients in the COVID-19 group were female and 13 (46.4%) were male. 15 (50%) of the patients in the control group were female and 15 (50%) male. 7 (25%) of the patients were categorized in Group 1, 14 (50%) in Group 2 and 7 (25%) in Group 3. There were no patients in Group 4.
The most common complaints of COVID-19-infected patients at the time of admission were weakness-fatigue (n=25, 89.3%), cough (n=23, 82.1%), muscle-joint pain (n=20, 71.4%), shortness of breath (n=19, 67.9%) and fever (n=13, 46.4%). Comorbidities were present in 15 (53.6%) of COVID-19-infected patients. The most common comorbidities were diabetes mellitus (n=7, 25%) and hypertension (n=6, 21.4%). Comparison of the laboratory parameters of the patients during hospitalization and discharge periods showed statistically significant differences in platelet, lactate dehydrogenase (LDH), CRP, alanine aminotransferase (ALT), urea, and creatinine levels (Table 1).
However, we found no statistically significant difference between GSDMD, caspase-1, IL-1p, and NLRP3 values during hospitalization and discharge periods. In addition, there was no statistically significant difference between the biomarkers of hospitalized COVID-19 patients and the biomarkers of the control group. However, it was observed that all of four biomarkers, more prominently at IL-1p level, were found to be higher in the patient group than the control group (Table 2).
The Kruskal-Wallis was performed to detect whether difference of GSDMD, caspase-1, IL-1p and NLRP3 levels were statistically significant between the COVID-19 patient groups. As a result of the test, it was determined that there were no statistically differences between the biomarkers according to the patient's groups. Although it could not be determined the significant differences, there were remarkable differences between the means of IL-1p values of the patient's groups. It was concluded that the reason of not determining the statistically significant differences was that the standard deviations were high (Table 3).
In the COVID-19 patient group, no statistically significant difference was found between the GSDMD, IL-1p, caspase-1, and NLRP3 values of patients with lymphopenia, leukopenia, and neutropenia at hospitalization and discharge. However, in patients with lymphopenia and leukopenia, while IL-1p and GSDMD levels increased at the discharge period, it was observed that caspase-1 and NLRP3 levels decreased (Table 4).
Table 1
Laboratory parameters of COVID-19 infected inpatients at admission day and discharge day
Parameters Admission day (n=28) Discharge day (n=28) p
Mean S.D Mean S.D
Leucocyte (cells/ mm3) 5835.67 2390.26 7060.42 3333.037 0.064
Neutrophil (cells/ mm3) 4206.67 2247.06 5283.75 3027.29 0.088
Lymphocyte (cells/ mm3) 1139.67 552.98 1516.79 950.75 0.079
Platelet (cells/mm3) 204.42 74.13 300.46 160.03 0.001
HGB (g/dL) 13.80 1.68 13.44 1.95 0.132
PT (seconds) 11.79 1.87 11.77 2.18 0.755
INR 0.95 0.15 0.96 0.18 0.776
D-Dimer (pg/mL ) 0.88 0.71 1.20 2.89 0.255
Fibrinogen(mg/dL) 422 251.72 409.57 163.43 0.913
Ferritin (ng/mL ) 391.13 530.29 657.00 611.75 0.262
LDH (U/L) 355.36 169.41 236.73 48.99 0.005
CRP (mg/dL) 5.47 7.34 1.84 2.18 0.011
ALT (U/L) 39.08 29.90 111.75 92.100 0.000
AST (U/L) 39.88 13.34 83.00 53.53 0.062
Urea (mg/dL) 31.58 12.17 36.88 10.99 0.031
Creatine (mg/dL) 0.86 0.23 0.75 0.16 0.006
Albumin (g/dL) 4.16 0.63 4.29 2.26 0.790
HGB: Hemoglobin, AST: Aspartate aminotransferase, PT: Prothrombin time, INR: International Normalized Ratio, SD: standard deviation
1 Comparison of GSDMD, Caspase-1, IL-1 ß and NLRP3 values of case and control groups on hospitalization day and discharge day
Admission day (n=58) Discharge day (n=58) p
Mean S.D Mean S.D
GSDMD 4.24 1.33 4.16 1.43 0.85
Caspase-1 5.24 3.86 5.92 5.71 0.96
IL-1ß 928.77 878.85 1335.45 1638.85 0.73
NLRP3 99.66 50.17 97.41 49.90 0.34
Comparison of biomarkers of the COVID-19 group with the control group on admission day
Control (n=30) COVID-19 patients' values on admission day (n=28) p
Mean S.D Mean S.D
GSDMD 3.67 0.98 4.24 1.33 0.30
Caspase-1 5.23 3.73 5.24 3.86 0.53
IL-1ß 828.06 613.02 928.77 878.85 0.94
NLRP3 86.57 34.48 99.66 50.17 0.79
Comparison of biomarkers of the COVID-19 group with the control group on disharge day
Control (n=30) COVID-19 patients' values on a disharge day (n=28) p
Mean S.D Mean S.D
GSDMD 3.67 0.98 4.16 1.43 0.13
Caspase-1 5.23 3.73 5.92 5.71 0.73
IL-1ß 828.06 613.02 1335.45 1638.77 0.98
NLRP3 86.57 34.48 97.41 49.90 0.97
It was compared biomarkers of patients with LDH>250 U/L and those with LDH<=250 U/L at the hospitalization period. As a result of comparisons, it was found that while IL-ip and caspase-1 values were higher at the discharge period, GSDMD and NLRP3 values were lower. However, these differences were not found statistically significant. When the biomarkers of
patients with and without the comorbidity were compared at the hospitalization and discharge periods, it was observed that there were no statistically significant differences between GSDMD, caspase-1, IL-ip and NLRP3 values. GSDMD, caspase-1, IL-ip, and NLRP3 values were higher in patients with comorbidities, both at the hospitalization and the discharge (Table 5).
Table 3
GSDMD, Caspase-1, IL-1p, NLRP3 values on the day of admission and discharge days
GSDMD, Caspase-1, IL-1ß, Group 1
(mildly symptomatic) (n=7)
NLRP3 values on the day of admission Group 2 (symptomatic) (radiological involvement in addition to fever and respiratory symptoms) (n=14)
Group 3
(symptomatic (dyspnea, oxygen saturation S93% at rest)) (n=7)
Mean
S.D
Mean
S.S
Mean
S.D
GSDMD Caspase-1 IL-1ß NLRP3
3.61 4.05 527.31 85.31
0.92 2.16 216.21 42.80
4.37 5.65 1141.90 107.37
1.08 3.75 956 46.16
4.60
5.61 903.96 98.59
1.98 5.47 1073.83 67.05
0.53 0.57 0.10 0.39
GSDMD, Caspase-1, IL-1ß, Group 1
(mildly symptomatic) (n=7)
NLRP3 values on the day of discharge Group 2 (symptomatic) (radiological involvement in addition to fever and respiratory symptoms) (n=14)
Group 3
(symptomatic (dyspnea, oxygen saturation S93% at rest)) (n=7)
Mean
S.D
Mean
S.D
Mean
S.D
GSDMD Caspase-1 IL-1ß NLRP3
4.59 3.77 594.44 83.92
0.88 1.59 286.55 36.79
3.75 4.95 1185.41 97.44
1.36 3.62 1232.72 50.06
4.55 10.03 2376.52 110.84
1.89 9.40 2598.63 63.22
0.15 0.42 0.61 0.69
p
GSDMD, Caspase-1, IL-1 p, NLRP3 values on the day of admission and discharge days in COVID-19 patients with lymphopeniajeukopenia and neutropenia GSDMD, Caspase-1, IL-1p, NLRP3 values on the day of admission and discharge days in COVID-19 patients with lymphopenia (n =28) Admission day_Discharge day_
Mean
S.D
Mean
S.D
GSDMD Caspase-1 IL-1ß NLRP3
4.17 6.00 970.05 109.97
1.51 4.66 854.26 58.79
4.67 5.94 1772.89 104.36
1.54 5.12 2118.20 59.17
0.64 0.51 0.12 0.35
GSDMD, Caspase-1, IL-ip, NLRP3 values on the day of admission and discharge days in COVID-19 patients with leukopenia (n=14)
Admission day
Discharge day
Mean
S.D
Mean
S.D
GSDMD Caspase-1 IL-1ß NLRP3
3.91 4.37 876.04 87.73
1.26 3.86 982.73 41.70
4.46 4.30 978.09 79.32
1.23 3.78 1317.66 35.59
0.48 0.89 0.58 0.16
GSDMD, Caspase-1, IL-1p, NLRP3 values on the day of admission and discharge days in COVID-19 patients with neutropenia (n=7)
Admission day
Discharge day
Mean
S.D
Mean
S.D
GSDMD Caspase-1 IL-1ß NLRP3
3.30 2.49 489.05 69.31
0.28 0.88 292.10 22.76
5.60 2.49 390.02 63.26
0.62 0.33 48.74 10.17
0.11 1.00 1.00 1.00
Table 5
Comparison of admission and discharge day biomarkers of patients with and without comorbidity
Comparison of the admission day biomarkers of patients with and without comorbidity
With Comorbidity (n=15) Without Comorbidity(n=13)
Mean S.D Mean S.D p
GSDMD 4.27 1.49 4.21 1.18 0.91
Caspaz-1 5.30 4.29 5.17 3.48 0.93
IL-1ß 1099.22 1124.30 732.09 430.00 0.79
NLRP3 88.61 41.92 112.41 57.30 0.22
Comparison of the discharge biomarkers of patients with and without comorbidity
With Comorbidity (n= 15) Without Comorbidity (n=13)
Mean S.D Mean S.D p
GSDMD 4.44 1.68 3.83 1.03 0.25
Caspase-1 6.83 6.72 4.88 4.29 0.86
IL-1ß 1421.72 1532.37 1235.90 1811.90 1.00
NLRP3 89.72 41.95 106.28 58.22 0.44
Discussion
The process of apoptosis was the first type of programmed cell death to be identified, and in most circumstances, caspase-3 and -7 ensure that it is immune-silent. In contrast, the lytic cell death mechanisms of necroptosis and pyroptosis permit the release of potential immunostimulatory chemicals. According to genetic evidence, these cell death pathways can initiate powerful inflammatory responses in vivo, which may contribute to the pathology of numerous inflammatory diseases. In some cases, the bystander DAMPs released after pyroptosis and necroptosis may be less inflammatory than if the cell did not get the cues for suicide. This may reflect cell-type and stimulus-specific pyroptotic and necroptotic signaling scenarios [20-24].
In this study, GSDMD, caspase-1, IL-ip and NLRP3 biomarkers were studied in patients and healthy volunteers with aim of examining the relationship between pyroptosis and COVID-19. In our study, it was detected that there were no statistically significant differences between the COVID-19 and control groups. When the reason of not detecting the significant differences was investigated, it was determined that the deviations between the biomarker values at the hospitalization and the discharge periods were high (high standard deviation) and it is concluded that these results could be caused by the limited population size. Although there were no statistically significant differences, the distribution of some biomarkers, especially IL-ip, between the groups was considered remarkable. Some findings can be summarized as follows: IL-ip level was found to be higher both at the hospitalization and at the discharge periods of COVID-19 patients when compared with the control group. This is thought to be an important indicator of the interaction between COVID-19 and the pyroptosis mechanism. When the patients with high CRP and those without CRP were compared at the hospitalization period, it was observed that all four parameters were higher in those with high CRP values. This suggests that there is a parallelism between the level of inflammation and pyroptosis. At the hospitalization period, the patients with high LDH levels had higher levels of IL-ip. It was observed that IL-ip levels increased as the severity of the COVID-19 increased according to observations obtained at the discharge period. Besides, all four biomarkers were higher in patients with comorbidity both at the hospitalization and at the discharge periods compared to those without comorbidity. This result suggested that other underlying diseases or factors may affect pyroptosis.
Induction of NOD-like receptor (nucleotide-binding oligomerization domain) activation by pathogen or alarmin results in activation of caspase-1. The proteolytic activation of caspase-1 catalyzes the maturation and secretion of proinflammatory cytokines, notably IL-ip and IL-i8. NLRP3, the best described among inflammasomes, has been associated with many diseases from autoinflammatory diseases to neurological disorders. NLRP3 also plays a role in antiviral responses and viral diseases [25,26]. There are six members of the gasdermin protein family, and each of them has different functions in human tissues and organs [27,28]. GSDMD is the most common and best studied protein in pyroptosis. GSDMD is cleaved by caspase-1/4/5/11 to release its C and N-terminal fragments. The lipophilic N-terminal disrupts the cell membrane transition balance resulting in K+ outflow to the extracellular space and Na+ entry into the intracellular space by constituting pores in the cell membrane. As a result, the cell swells, the membrane ruptures, and the contents are released out of the cell, causing an intense inflammatory response with pyroptosis [i5]. Previous studies have reported that pyroptosis may also cause a strong inflammatory response and clear or reduce cells through division, consistent with symptoms after SARS-CoV-2 infection. There is increasing evidence showing that pyroptosis may play a role in SARS-CoV-2 infection and its pathogenesis [15,29,30]. Xu et al. [18] investigated the relationship between pyroptosis
and the severity of COVID-19. In this study, single-cell RNA-seq (scRNAseq) data of 37,607 immune system cells belonging to eight different cell types from four studies were analyzed. As a result of the study, it was determined that the expression of key markers of pyroptosis, such as IL-ip and ILi8, was significantly higher in moderate and severe COVID-19 patients than in healthy volunteers. It was observed that caspase-1 was overexpressed in the spleen of hDPP4-Tg (human dipeptidyl peptidase 4 transgenic) mice infected with this virus and elevated levels of IL-ip in the serum. In addition to this, in this study, it was shown that the expression of caspase-i and IL-ip decreased as a result of blockade of C5a-C5aR1 by an anti-C5aR1 antibody. Based on these data, it has been suggested that MERS-CoV infection induces overactivation of complement, which may contribute to pyroptosis and inflammation, and that C5aRi may inhibit pyroptosis [31]. Chen et al [32] have stated that SARS-CoV Viroporin 3a activates the NLRP3 inflammasome, triggers IL-ip secretion in bone marrow-derived macrophages, and this suggested cell pyroptosis caused by SARS-CoV.
In our study, it was detected that there were no statistically significant differences between the biomarkers as a result of the mean comparison tests. However, it was observed that the IL-ip levels between groups of the control, the hospitalization, and the discharge were found to be remarkable: in the COVID-19 group, the IL-ip level at the discharge was higher than at the hospitalization; IL-ip levels of the COVID-i9 group at both the hospitalization and the discharge periods were higher than the control group. Although statistically significant differences were not detected in our study, the higher IL-ip level in the patient group was considered as an immunological finding supporting the relationship between COVID-19 and pyroptosis. In addition, GSDMD, caspase-i, IL-ip and NLRP3 values were found to be higher in patients having high CRP at the hospitalization period. It was thought that this may be an important indicator of the parallelism between inflammation and pyroptosis. High levels of LDH are a general sign of tissue damage, which is supported by the widespread cell death of monocytes, alveolar epithelial cells, lung, and kidney endothelial cells. These cells are also competent to play a role in inflammasome activation and pyroptosis [33-38]. It has been shown that IL-1 family cytokines, LDH level and high GSDMD expression, which are considered as signs of pyroptosis in plasma, are associated with increasing risk of serious COVID-19 disease [38,39]. Kayagaki et al. [40] showed that IL-ip secretion decreased and release of LDH impaired as a result of blocking the GSDMD pathway in mice. In our study, the high IL-ip level in patients with high LDH level at the hospitalization period supports the relationship between pyroptosis and COVID-19, and in this respect, it is similar to the literature [41-45].
It has been shown that pyroptosis not only has an important role in infectious diseases, cardiovascular diseases, tumors, central nervous system diseases [39-43]. In addition, it has been shown that pyroptosis also plays an important role in the development of spontaneous inflammatory diseases, autoimmune diseases (systemic lupus erythematosus, inflammatory bowel diseases) and various metabolic diseases [46,47]. In our study, GSDMD, caspase-i, IL-ip and NLRP3 values have been found to be higher in patients with comorbidities both at the hospitalization and the discharge periods. This result is thought to be an important indicator that comorbid factors may affect pyroptosis.
Inflammation is induced by the inflammasomes. They have been linked to a number of inflammatory diseases. Our understanding of the processes by which the NLRP3 inflammasome is activated has significantly improved in light of recent evidence. Inflammasome involvement in the onset or progression of diseases with significant effects on public health, such as metabolic pathologies (obesity, type 2 diabetes, atherosclerosis), cardiovascular diseases (ischemic and non-
ischemic heart disease), inflammatory conditions (liver diseases, inflammatory bowel diseases, gut microbiome, rheumatoid arthritis), and neurologic disorders is also strongly supported by growing evidence in animal models and human studies [48]. In this study, the inadequacy of the study population, the heterogeneous distribution of measurements, and not studying of IL-18, another important cytokine released together with IL-ip in the pyroptosis mechanism, are the important limitations of our study.
Conclusion
Despite the decrease in the number of cases, the COVID-19 pandemic continues to maintain its importance. Different studies have been conducted on the etiopathogenesis, and pyroptosis, which is one of the cell death mechanisms, is one of them. In our study, IL-ip, which is one of the cytokines released as a result of cell death in the pyroptosis mechanism, was found to be higher in patients with a diagnosis of COVID-19 both at the hospitalization and the discharge compared to the control group. The high IL-ip level in patients with high LDH levels was
another important finding supporting the relationship between pyroptosis and COVID-19. Studies on these pyroptosis-associated markers with larger patient population and different patient groups are needed.
Ethics Committee approval
Harran University, Medicine Faculty Ethics Committee was received the approval (29/11/2021, HRU/21.21.09). All procedures were performed in accordance with the Declaration of Helsinki.
Disclosures: There is no conflict of interest for all authors. Acknowledgements: None. Funding: None.
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