Macroporous resin adsorption column chromatography, silica gel column chromatography, ODS column chromatography, and semi-preparative high-performance liquid chromatography, combined with analytical methods such as NMR and MS, were employed to separate and identify compounds from the 70% ethanol extract of Ajania purpurea. A total of 30 compounds were isolated and identified, including 13 phenolic acids, 7 coumarins, 2 lignans, 1 flavonoid, 2 sesquiterpenes, 1 steroid, and 4 others. Among them, compounds 1 and 2 were newly discovered compounds, and compounds 4, 6, 8, 12, 14-23, 25, 28, and 30 were isolated from Ajania plants for the first time. Bioactivity screening showed that multiple compounds significantly inhibited the production of nitric oxide in lipopolysaccharide-stimulated RAW264.7 cells in a dose-dependent manner. Furthermore, compound 2 elevated the levels of glutathione in LPS-induced BEAS-2B cells, reduced the expression of pro-inflammatory cytokines such as tumor necrosis factor(TNF)-α, interleukin(IL)-6, and IL-1β, enhanced the mRNA of GPX4, HMOX1, NFE2L2, and enhanced protein levels of GPX4, HO-1, Nrf2, and SLC7A11, demonstrating potential anti-ferroptotic effect.
Mice ; Animals ; Lignans/isolation & purification* ; RAW 264.7 Cells ; Humans ; Nitric Oxide ; Tumor Necrosis Factor-alpha/immunology* ; Drugs, Chinese Herbal/isolation & purification* ; NF-E2-Related Factor 2/metabolism* ; Macrophages/metabolism* ; Interleukin-6/immunology*

OBJECTIVE: To investigate the effect of mild hypothermia on neurological function in rats with spinal cord injury (SCI) based on the adenosine monophosphate activated protein kinase (AMPK)/Nod-like receptor protein 3 (NLRP3) pathway. METHODS: Fifty 7-8 weeks old SPF male Sprague Dawley rats were used to establish rat model of SCI by Allen's method. Among them, 48 successfully modeled rats were randomly divided into SCI group, mild hypothermia group (SCI+mild hypothermia treatment), and Compound C group (SCI+mild hypothermia+intraperitoneal injection of 20 mg/kg AMPK/NLRP3 pathway inhibitor Compound C), with 16 rats in each group. Another 16 normal rats with laminectomy were selected as sham-operation group. Basso-Beattie-Bresnahan (BBB) score was used to evaluate the motor ability of rats at 1, 3, 7, 14 days after treatment. After 14 days, the rats were sacrificed, and the spinal cord histopathological morphology was observed by HE staining, the neuronal apoptosis in spinal cord tissue was detected by TUNEL assay, and the serum levels of interleukin 2 (IL-2), IL-6, transforming growth factor β ₁ (TGF-β ₁), malondialdehyde (MDA), and superoxide dismutase (SOD) were detected by ELISA. The expressions of AMPK/NLRP3 pathway proteins in spinal cord tissue, including B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), and cleaved-Caspase-9 were detected by Western blot. RESULTS: At 1 day after treatment, the rats in SCI group, mild hypothermia group, and Compound C group did not recover their motor ability. With the prolongation of time, the motor function of rats in each group gradually recovered. Among them, the BBB score of SCI group was significantly lower than that of sham-operation group and mild hypothermia group ( P<0.05), and the BBB score of Compound C group was significantly lower than that of mild hypothermia group ( P<0.05). Compared with the sham-operation group, the SCI group displayed obvious pathological changes in the spinal cord tissue, with disordered tissue architecture, inflammatory infiltration, and blurred interstitial boundaries. The neuronal apoptosis rate, Bax/Bcl-2 ratio, cleaved Caspase-9 expression, NLRP3 protein expression, serum IL-2, IL-6, and MDA levels were elevated, whereas serum TGF-β ₁, SOD levels, and spinal cord phosphorylation AMPK/AMPK protein expression significantly decreased ( P<0.05). Compared with the SCI group, the above phenomena significantly improved in the mild hypothermia group ( P<0.05), while the Compound C group showed the opposite trend of change compared to the mild hypothermia group ( P<0.05). CONCLUSION Mild hypothermia can attenuate neurological dysfunction after SCI in rats, potentially by activating the AMPK/NLRP3 pathway.
Animals ; Spinal Cord Injuries/physiopathology* ; Rats, Sprague-Dawley ; Male ; Rats ; NLR Family, Pyrin Domain-Containing 3 Protein/metabolism* ; AMP-Activated Protein Kinases/metabolism* ; Hypothermia, Induced ; Signal Transduction ; Spinal Cord/pathology* ; Apoptosis ; Interleukin-6/metabolism* ; Disease Models, Animal ; bcl-2-Associated X Protein/metabolism* ; Superoxide Dismutase/metabolism* ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; Caspase 9/metabolism*

Objective To explore the characteristics of the inhibitory effect of Evodiamine on the proliferation of activated T cells. Methods Mononuclear cells from peripheral blood (PBMCs) were obtained from healthy donors through density gradient centrifugation, and T cells were subsequently purified by using immunomagnetic bead separation. T cell activation was induced by employing anti-human CD3 and anti-human CD28 antibodies. T cells were treated with different concentrations of EVO (0.37, 1.11, 3.33, and 10)μmol/L. Flow cytometry was applied to evaluate the proliferation index, apoptosis rate, viability, CD25 expression levels, and cell cycle distribution of T cells. The expression levels of cytokines IL-2, IL-17A, IL-4, and IL-10 were quantified by using ELISA. Results 1.11, 3.33 and 10 μmol/L EVO effectively inhibited the proliferation of activated T cells, with an IC₅₀ of (1.5±0.3)μmol/L. EVO did not induce apoptosis in activated T cells and affect the survival rate of resting T cells. EVO did not affect the expression of CD25 and the secretion of IL-2 in activated T cells. EVO arrested the T cell cycle at the G2/M phase, resulting in an increase in G2/M phase cells, and exhibited a concentration-dependent effect. EVO did not affect the secretion of IL-4, IL-10 by activated T cells, but significantly inhibited the secretion of IL-17A. Conclusion EVO did not significantly affect the activation process of T cells but inhibited T cell proliferation by arresting the cell cycle at the G2/M phase and significantly suppressed the secretion of the pro-inflammatory cytokine IL-17A, which suggests that EVO has the potential to serve as a lead compound for the development of low-toxicity and high-efficiency immunosuppressants and elucidates the mechanisms underlying the anti-inflammatory and immunomodulatory effects of the traditional Chinese medicine Evodia rutaecarpa.
Humans ; Cell Proliferation/drug effects* ; Quinazolines/pharmacology* ; T-Lymphocytes/metabolism* ; Lymphocyte Activation/drug effects* ; Apoptosis/drug effects* ; Interleukin-4/metabolism* ; Interleukin-10/metabolism* ; Interleukin-2 Receptor alpha Subunit/metabolism* ; Interleukin-17/metabolism* ; Interleukin-2/metabolism* ; Cell Cycle/drug effects* ; Cells, Cultured

Objective The study aims to investigate the immunological functions of the nucleocapsid (N) protein of the novel coronavirus Omicron (BA.1, BA.2) and evaluate the differences among different N proteins of mutant strains in immunogenicity. Methods By aligning sequences, the mutation sites of the Omicron (BA.1, BA.2) N protein relative to prototype strain of the novel coronavirus (Wuhan-Hu-1) were determined. The pET-28a-N-Wuhan-Hu-1 plasmid was used as template to construct pET-28a-BA.1/BA.2-N through single point mutation or homologous recombination. The three kinds of N protein were expressed in prokaryotic system, purified through Ni-NTA affinity chromatography, and then immunized into mice. The titer and reactivity of the polyclonal antibody, as well as the expression level of IL-1β and IFN-γ in mouse spleen cells, were detected using indirect ELISA and Western blot assay. Results The constructed prokaryotic expression plasmids were successfully used to express the Wuhan-Hu-1 N, BA.1 N, and BA.2 N proteins in E.coli BL21(DE3) at 37 DegreesCelsius for 4 hours. The indirect ELISA test showed that the titers of polyclonal antibody prepared by three N proteins were all 1:51 200. All three N proteins can increase the expression of IFN-γ and IL-1β cytokines, but the effect of Omicron N protein in activing two cytokines was more obvious than that of Wuhan-Hu-1 N protein. Conclusion The study obtained three new coronavirus N proteins and polyclonal antibodies, and confirmed that mutations in the amino acid sites of the N protein can affect its immunogenicity. This provides a basis for developing rapid diagnostic methods targeting N protein of different novel coronavirus variants.
Animals ; Mice ; SARS-CoV-2/genetics* ; Coronavirus Nucleocapsid Proteins/immunology* ; Nucleocapsid Proteins/isolation & purification* ; COVID-19/immunology* ; Antibodies, Viral/immunology* ; Mice, Inbred BALB C ; Interferon-gamma/metabolism* ; Interleukin-1beta/metabolism* ; Female ; Escherichia coli/metabolism* ; Mutation ; Humans

Objective To investigate the effect of ATP synthase inhibitory factor 1 (ATPIF1) on the antitumor activity of chimeric antigen receptor (CAR)-NK92 cells. Methods HER2-targeted CAR-NK92 cells with ATPIF1 overexpression or knockdown were constructed. CAR-positive expression rate was detected by flow cytometry. Cell proliferation capacity was measured using CCK-8 assay. Glycolytic capacity was analyzed by Seahorse metabolic analyzer. Mitochondrial membrane potential levels were detected using JC-1 probe. Target cell lysis rate was evaluated by firefly luciferase reporter assay. Expression levels of CD107a, natural-killer group 2 member D (NKG2D), granzyme B (GzmB), perforin, and interleukin 2 (IL-2) were detected via flow cytometry. Quantitative real-time PCR was used to measure the expression of interferon-induced protein with tetratricopeptide repeats 1 (IFIT1), tumor necrosis factor α (TNF-α), ATPIF1, and hexokinase 1 (HK1). The impact of glycolytic inhibition by 2-Deoxy-D-glucose (2-DG) on CAR-NK92 antitumor capacity was examined. Results Successfully generated HER2-targeting control CAR-NK92 cells, as well as ATPIF1-overexpressing and ATPIF1 knockdown CAR-NK92 cells. The ATPIF1-overexpressing CAR-NK92 cells showed significantly enhanced target cell lysis rate, elevated expression levels of NKG2D and CD107a, increased secretion capacities of Granzyme B (GzmB) and IL-2, and upregulated mRNA expression levels of IFIT1 and TNF-α, while ATPIF1-knockdown cells exhibited opposite effects. ATPIF1 overexpression induced metabolic reprogramming in CAR-NK92 cells, manifested by significantly decreased mitochondrial membrane potential (δpsim), markedly upregulated HK1 mRNA expression, and enhanced basal glycolysis and glycolytic capacity. After glycolysis inhibition with 2-DG (5 μmol/L), both ATPIF1-overexpressing and knockdown CAR-NK92 cells showed no significant differences in NKG2D and CD107a expression levels compared to control cells. Conclusion ATPIF1 regulates the antitumor activity of CAR-NK92 cells through modulating glycolytic metabolism. Overexpression of ATPIF1 can enhance the antitumor efficacy of CAR-NK92 cells.
Humans ; Glycolysis ; Killer Cells, Natural/metabolism* ; Receptors, Chimeric Antigen/immunology* ; Granzymes/genetics* ; Hexokinase/metabolism* ; Cell Line, Tumor ; Interleukin-2/genetics* ; Cell Proliferation ; NK Cell Lectin-Like Receptor Subfamily K/genetics* ; Membrane Potential, Mitochondrial

OBJECTIVES: To investigate the role and mechanism of fibroblast growth factor (FGF) 19 in inflammation-induced injury of vascular endothelial cells caused by high glucose (HG). METHODS: Human umbilical vein endothelial cells (HUVECs) were randomly divided into four groups: control, HG, FGF19, and HG+FGF19 (n=3 each). The effect of different concentrations of glucose and/or FGF19 on HUVEC viability was assessed using the CCK8 assay. Flow cytometry was utilized to examine the impact of FGF19 on HUVEC apoptosis. Levels of interleukin-6 (IL-6), inducible nitric oxide synthase (iNOS), total superoxide dismutase (T-SOD), and malondialdehyde (MDA) were measured by ELISA. Real-time quantitative PCR and Western blotting were used to determine the mRNA and protein expression levels of vascular endothelial growth factor (VEGF), nuclear factor erythroid 2 related factor 2 (Nrf2), and heme oxygenase-1 (HO-1). Cells were further divided into control, siRNA-Nrf2 (siNrf2), HG, HG+FGF19, HG+FGF19+negative control, and HG+FGF19+siNrf2 groups (n=3 each) to observe the effect of FGF19 on oxidative stress injury in HUVECs induced by high glucose after silencing the Nrf2 gene. RESULTS: Compared to the control group, the HG group exhibited increased apoptosis rate, increased IL-6, iNOS and MDA levels, and increased VEGF mRNA and protein expression, along with decreased T-SOD activity and decreased mRNA and protein expression of Nrf2 and HO-1 (P<0.05). Compared to the HG group, the HG+FGF19 group showed reduced apoptosis rate, decreased IL-6, iNOS and MDA levels, and decreased VEGF mRNA and protein expression, with increased T-SOD activity and increased Nrf2 and HO-1 mRNA and protein expression (P<0.05). Compared to the HG+FGF19+negative control group, the HG+FGF19+siNrf2 group had decreased T-SOD activity and increased MDA levels (P<0.05). CONCLUSIONS FGF19 can alleviate inflammation-induced injury in vascular endothelial cells caused by HG, potentially through the Nrf2/HO-1 signaling pathway.
Humans ; NF-E2-Related Factor 2/genetics* ; Signal Transduction ; Human Umbilical Vein Endothelial Cells/drug effects* ; Fibroblast Growth Factors/pharmacology* ; Heme Oxygenase-1/physiology* ; Apoptosis/drug effects* ; Glucose ; Inflammation ; Interleukin-6/analysis* ; Vascular Endothelial Growth Factor A/genetics* ; Nitric Oxide Synthase Type II/analysis* ; Cells, Cultured

OBJECTIVE: To investigate the predictive value of serum soluble interleukin-2 receptor(sIL-2R), tumor necrosis factor alpha(TNF-α), IgG and IgA for the recurrence in patients with multiple myeloma(MM). METHODS: A total of 108 MM patients who were initially diagnosed and treated in our hospital from January 2017 to March 2019, and 72 patients who met the diagnostic criteria and had complete follow-up data were selected as the study subjects. MM recurrence was the endpoint event, and follow-up was conducted until the occurrence of the endpoint event or the deadline of this study. MM patients were divided into recurrent group(RG) and non-recurrent group(NRG) based on whether they have relapsed or not. Venous blood was collected from patients at the first diagnosis and follow-up (at the occurrence of endpoint events or termination of the study), and enzyme-linked immunosorbent assay(ELISA) was used to detect sIL-2R and TNF-α levels in the patient's serum. An automatic immune analyzer was used to detect the levels of IgG and IgA in the patient's serum. The differences in expression levels of the factors between two groups were compared and the correlations between sIL-2R and TNF-α, IgG and IgA at the first diagnosis and follow-up were analyzed. At the same time, venous blood was collected from patients during complete remission, and their serum sIL- 2R levels were measured to compare the differences in sIL-2R expression levels at the first diagnosis, complete remission and recurrence. Receiver operating characteristic(ROC) curves was used to determine the optimal cutoff values for serum sIL-2R, TNF-α, IgG and IgA, and the predictive value of sIL-2R, TNF-α, IgG and IgA in the recurrence of MM patients were analyzed based on the area under the curve(AUC). RESULTS: The serum sIL-2R levels of MM patients at the first diagnosis and recurrence were significantly higher than at complete remission (P < 0.05). At the first diagnosis, the hemoglobin content of RG was lower than that of NRG, while the β₂-microglobulin content was higher than that of NRG (P < 0.001). There was no significant difference in other clinical parameters between the two groups (P >0.05). The levels of sIL-2R, TNF-α, IgG and IgA at the first diagnosis and follow-up of RG were higher than those of NRG (P < 0.05). There was a significant correlation between sIL-2R and TNF-α, IgG and IgA at the first diagnosis and follow-up (P < 0.001). The ROC curve showed that, at the first diagnosis, sIL-2R, TNF-α, IgG and IgA predicted the AUC of MM patients were 0.919, 0.850, 0.766 and 0.795, respectively, after follow-up, they predicted AUC of MM were 0.890, 0.815, 0.760 and 0.794, respectively (P < 0.001). CONCLUSION The serum sIL-2R has the highest predictive value for MM patient's recurrence, and it is possible to detect the TNF-α, IgG and IgA levels at specific times to infer changes in sIL-2R levels and evaluate the patient's prognosis.
Humans ; Multiple Myeloma/blood* ; Immunoglobulin A/blood* ; Immunoglobulin G/blood* ; Tumor Necrosis Factor-alpha/blood* ; Receptors, Interleukin-2/blood* ; Recurrence ; Male ; Female ; Neoplasm Recurrence, Local ; Middle Aged ; Prognosis

OBJECTIVE: To explore the expression and clinical significance of programmed death receptor 1 (PD-1), Th1, Th2, and Th17 cytokines in multiple myeloma (MM). METHODS: A total of 76 MM patients treated in the Tengzhou Central People's Hospital from May 2021 to May 2023 were collected as MM group, and 48 healthy individuals who underwent physical examination during the same period were included as control group. The expression of PD-1 on the surface of CD4⁺ and CD8⁺ T cells and the levels of serum Th1 cytokines ［interleukin (IL) -2, interferon γ (IFN-γ), tumor necrosis factor α (TNF-α)］, Th2 cytokines (IL-4, IL-6, IL-10) and Th17 cytokines (IL-17) were detected in the two groups. Spearman correlation was used to examine the relationship between PD-1, Th1, Th2 and Th17 cytokines and clinical stage and immune typing of MM patients. Multivariate logistic regression analysis was used to analyze the related factors affecting the efficacy of chemotherapy in MM patients, and the factors were tested for multicollinearity. Receiver operating characteristic (ROC) curve was drawn to analyze the predictive value of PD-1, Th1, Th2 and Th17 cytokines in chemotherapy efficacy of MM patients. RESULTS: The levels of CD4⁺T PD-1, CD8⁺T PD-1, IL-4, IL-6, IL-10, and IL-17 in the MM group were higher than those in the control group, while the levels of IL-2, IFN-γ, and TNF-α were lower (all P <0.001). The levels of CD4⁺T PD-1, CD8⁺T PD-1, IL-4, IL-6, IL-10, and IL-17 in R-ISS stage III patients were higher than those in stage II and I patients, and the levels in stage II patients were higher than those in stage I patients (all P <0.05). The IL-2 level in R-ISS stage III patients was lower than that in stage II and I patients, and IL-2 level in R-ISS stage II patients was lower than that in stage I patients (all P <0.05). The levels of CD4⁺T PD-1, CD8⁺T PD-1, IL-4, IL-6, IL-10, and IL-17 in IgG patients were higher than those in IgA, light chain, and non secretory patients, while the level of IL-2 was lower (all P <0.05). Correlation analysis showed that CD4⁺T PD-1, CD8⁺T PD-1, IL-4, IL-6, IL-10, and IL-17 were positively correlated with R-ISS staging in MM patients (r =0.623, 0.635, 0.728, 0.330, 0.742, 0.412), and negatively correlated with immune classification (r =-0.664, -0.756, -0.642, -0.479, -0.613, -0.323). IL-2 was negatively correlated with R-ISS staging in MM patients (r =-0.280), and positively correlated with immune classification (r =0.483). The levels of CD4⁺T PD-1, CD8⁺T PD-1, IL-4, IL-6, IL-10, and IL-17 in the non-remission group were higher than those in the remission group, while the level of IL-2 was lower (all P <0.001). Multivariate logistic regression analysis showed that the increased CD4⁺T PD-1, CD8⁺T PD-1, IL-4, IL-6, IL-10 and IL-17 were risk factors for the efficacy of chemotherapy in MM patients (OR >1, P <0.05), while the increased IL-2 was a protective factor (OR < 1, P <0.05). The results of multicollinearity test showed that the tolerance of the seven factors included was between 0.714-0.885, and the variance inflation factor was between 1.130-1.400. There was no multicollinearity. The ROC curve analysis results showed that the area under the curve for the combined prediction of chemotherapy efficacy in MM patients by the above 7 factors was 0.942, with specificity of 0.741 and sensitivity of 0.909. CONCLUSION The expression levels of PD-1 on the surface of CD4⁺ and CD8⁺ T cells and serum Th2 and Th17 cytokines in MM patients are high, while Th1 cytokines are low. PD-1, Th1, Th2, and Th17 cytokines are related to clinical stage and immune classification of MM patients. The combined detection of these indicators can help predict the chemotherapy efficacy of MM patients.
Humans ; Programmed Cell Death 1 Receptor/metabolism* ; Multiple Myeloma/blood* ; Cytokines/metabolism* ; Th17 Cells/metabolism* ; Th1 Cells/metabolism* ; Th2 Cells/metabolism* ; Female ; Male ; Interleukin-10 ; Interferon-gamma ; Middle Aged ; Interleukin-17 ; Interleukin-2 ; Interleukin-4 ; Tumor Necrosis Factor-alpha ; Interleukin-6 ; Aged

OBJECTIVE: To investigate the biological activity and antitumor effect of pegylated recombinant human interleukin 2 (PEG-rhIL-2) obtained by site-specific conjugation of polyethylene glycol (PEG) with non-natural amino acids, and to explore its antitumor mechanism. METHODS: The binding activities of PEG-rhIL-2 at three different sites (T41, Y45, and V91) to human interleukin 2 receptors α (IL-2R_α) and β (IL-2R_β) and were detected by surface plasmon resonance (SPR) technology. Western blot was used to detect the levels of the Janus kinase-signal transducer and activator of transcription 5 (JAK-STAT5) signaling pathway activated by different doses of rhIL-2 and PEG-rhIL-2 in CTTL-2 and YT cells. Blood was collected after a single administration in mice to detect the drug concentration at different time points and evaluate the pharmacokinetic parameters of Y45-PEG-rhIL-2. Mouse hepatoma cell line Hepa1-6, pancreatic cancer cell line Pan-02, and colon cancer cell line MC-38 were selected. Tumor models were constructed in C57BL/6 mice. Different doses of Y45-PEG-rhIL-2 and excipient control were administrated respectively to evaluate the tumor suppression effect of the drug. In the MC-38 colon cancer model, the tumor suppression effect of Y45-PEG-rhIL-2 combined with anti-programmed death-1 (PD-1) monoclonal antibody was evaluated. Hepa1-6 mouse tumor models were constructed and rhIL-2, Y45-rhIL-2 and Y45-PEG-rhIL-2 were administrated respectively. The proportion of tumor-infiltrating lymphocytes was analyzed by flow cytometry. RESULTS: The SPR detection results showed that the binding activities of PEG-rhIL-2 to IL-2R_α/IL-2R_β were both reduced. The affinity of Y45-PEG-rhIL-2 to IL-2R_α was reduced to approximately 1/250, and its affinity to IL-2R_β was reduced to 1/3. Western blot results showed that the activity of Y45-PEG-rhIL-2 in stimulating JAK-STAT5 signaling in CTLL-2 cells expressing heterotrimeric IL-2 receptor complex IL-2R_αβγwas reduced to approximately 1/300, while its activity in YT cells expressing heterodimeric IL-2 receptor complex IL-2R_βγwas reduced to approximately 1/3. The pharmacokinetic evaluation after a single dose in the mice showed that the elimination half-life of Y45-PEG-rhIL-2 was 17.7 h. Y45-PEG-rhIL-2 has pharmacokinetic characteristics superior to those of rhIL-2. Y45-PEG-rhIL-2 showed dose-dependent tumor suppression activity, and the combination of Y45-PEG-rhIL-2 and anti-PD-1 antibody had a better tumor-inhibiting effect than the single use of Y45-PEG-rhIL-2 or anti-PD-1 antibody. Flow cytometry analysis demonstrated that 72 h after the administration of Y45-PEG-rhIL-2, the proportion of tumor-infiltrating cytotoxic T lymphocytes (CD8⁺T cells) increased by 86.84%. At 120 h after administration, the ratio of CD8⁺T cells to regulatory T cells (Treg) increased by 75.10%. CONCLUSION Y45-PEG-rhIL-2 obtained by site-specific conjugation via non-natural amino acids changed its receptor binding activity and inhibited tumor growth in dose-dependent manner in multiple tumor models by regulating CD8⁺T cells.
Interleukin-2/pharmacokinetics* ; Animals ; Mice ; Humans ; Recombinant Proteins/pharmacology* ; Polyethylene Glycols/chemistry* ; Cell Line, Tumor ; Antineoplastic Agents/pharmacokinetics* ; Signal Transduction/drug effects* ; STAT5 Transcription Factor/metabolism* ; Interleukin-2 Receptor alpha Subunit/metabolism* ; Interleukin-2 Receptor beta Subunit/metabolism*

Coronavirus disease 2019 (COVID-19) is a multi-system disease that can lead to various severe complications. Acute limb ischemia (ALI) has been increasingly recognized as a COVID-19-associated complication that often predicts a poor prognosis. However, the pathophysiology and molecular mechanisms underlying COVID-19-associated ALI remain poorly understood. Hypercoagulability and thrombosis are considered important mechanisms, but we also emphasize the roles of vasospasm, hypoxia, and acidosis in the pathogenesis of the disease. The angiotensin-converting enzyme 2 (ACE2) pathway, inflammation, and platelet activation may be important molecular mechanisms underlying these pathological changes induced by COVID-19. Furthermore, we discuss the hypotheses of risk factors for COVID-19-associated ALI from genetic, age, and gender perspectives based on our analysis of molecular mechanisms. Additionally, we summarize therapeutic approaches such as use of the interleukin-6 (IL-6) blocker tocilizumab, calcium channel blockers, and angiotensin-converting enzyme inhibitors, providing insights for the future treatment of coronavirus-associated limb ischemic diseases.
Humans ; COVID-19/physiopathology* ; Ischemia/etiology* ; SARS-CoV-2 ; Extremities/blood supply* ; Risk Factors ; Interleukin-6/antagonists & inhibitors* ; Acute Disease ; Angiotensin-Converting Enzyme 2