BACKGROUND: Severe COVID-19 is uncommon, restricted to 19% of the total population. In response to the first virus wave (alpha variant of SARS-CoV-2), we investigated whether a biomarker indicated severity of disease and, in particular, if variable expression of angiotensin converting enzyme 2 (ACE2) in blood might clarify this difference in risk and of post COVID -19 conditions (PCC).
METHODS: The IRB-approved study compared patients hospitalized with severe COVID-19 to healthy controls. Severe infection was defined requiring oxygen or increased oxygen need from baseline at admission with positive COVID-19 PCR. A single blood sample was obtained from patients within a day of admission. ACE2 RNA expression in blood cells was measured by an RT-PCR assay. Plasma ACE1 and ACE2 enzyme activities were quantified by fluorescent peptides. Plasma TIMP-1, PIIINP and MMP-9 antigens were quantified by ELISA. Data were entered into REDCap and analyzed using STATA v 14 and GraphPad Prism v 10.
RESULTS: Forty-eight patients and 72 healthy controls were recruited during the pandemic. ACE2 RNA expression in peripheral blood mononuclear cells (PBMC) was rarely detected acutely during severe COVID-19 but common in controls (OR for undetected ACE2: 12.4 [95% CI: 2.62-76.1]). ACE2 RNA expression in PBMC did not determine plasma ACE1 and ACE2 activity, suggesting alternative cell-signaling pathways. Markers of fibrosis (TIMP-1 and PIIINP) and vasculopathy (MMP-9) were additionally elevated. ACE2 RNA expression during severe COVID-19 often responded within hours to convalescent plasma. Analogous to oncogenesis, we speculate that potent, persistent, cryptic processes following COVID-19 (the renin-angiotensin system (RAS), fibrosis and vasculopathy) initiate or promote post-COVID-19 conditions (PCC) in susceptible individuals.
CONCLUSIONS: This work elucidates biological and temporal plausibility for ACE2, TIMP1, PIIINP and MMP-9 in the pathogenesis of PCC. Intersection of these independent systems is uncommon and may in part explain the rarity of PCC.

Radiotherapy (RT) may have a cardiotoxic effect on the heart and cardiovascular system. Postulated mechanisms mediating these complications include vascular endothelium damage and myocardial fibrosis. The aim of our study was to assess endothelial damage and myocardial fibrosis in the early period after RT on the basis of cardiac biomarkers and in relation to the radiation dose applied to individual heart structures in patients treated for non-small-cell lung cancer. This single-center prospective study included consecutive patients with lung cancer (LC) who were referred for treatment with radiochemotherapy (study group) or chemotherapy (control group). The study protocol included performing an echocardiographic examination, a standard ECG examination, and collecting blood samples for laboratory tests before starting treatment for lung cancer in the first week after completing RT (after four cycles of chemotherapy in the control group) and after 12 weeks from the end of treatment. The study included 23 patients in the study group and 20 patients in the control group. Compared to the baseline values, there was a significant increase in total cholesterol concentration in the study group immediately after the end of RT, which persisted for three months after the end of therapy. After taking into account the use of statins in the analysis, it was found that an increase in total cholesterol concentration after oncological treatment was observed only among patients who did not use statins. Taking into account the assessment of myocardial fibrosis markers, there were no significant changes in the concentration of matrix metallopeptidase 9 (MMP-9) and tissue inhibitors of metalloproteinases 1 (TIMP-1) in the study group. In patients treated with radiochemotherapy, there was a significant increase in the concentration of intercellular adhesion molecule 1 (ICAM-1) immediately after RT, when compared to the baseline. After taking into account the use of statins, an increase in ICAM-1 concentration immediately after RT was observed only in patients who did not use statins. There was also a significant correlation between the radiation dose received by the left anterior descending coronary artery (LAD) and left circumferential coronary artery, and vascular cell adhesion protein 1 (VCAM-1) concentration measured at three months after the end of RT. Immediately after completion of radiotherapy, a significant increase in the level of ICAM-1 is observed indicating endothelial damage. The radiation dose to coronary arteries should be minimized, as it correlates with the concentration of VCAM-1. The use of statins may prevent the increase in total cholesterol and ICAM-1 concentration after irradiation for lung cancer; however, further studies designed for this specific purpose are necessary to confirm the effectiveness of statins in this area.

Bosentan, an endothelin receptor antagonist (ERA), has potential anti-atherosclerotic properties. We investigated the complementary effects of bosentan and atorvastatin on the progression and composition of the atherosclerotic lesions in diabetic mice. Forty-eight male ApoE-/- mice were fed high-fat diet (HFD) for 14 weeks. At week 8, diabetes was induced with streptozotocin, and mice were randomized into four groups: (1) control/COG: no intervention; (2) ΒOG: bosentan 100 mg/kg/day per os; (3) ATG: atorvastatin 20 mg/kg/day per os; and (4) BO + ATG: combined administration of bosentan and atorvastatin. The intra-plaque contents of collagen, elastin, monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-a (TNF-a), matrix metalloproteinases (MMP-2, -3, -9), and TIMP-1 were determined. The percentage of lumen stenosis was significantly lower across all treated groups: BOG: 19.5 ± 2.2%, ATG: 12.8 ± 4.8%, and BO + ATG: 9.1 ± 2.7% compared to controls (24.6 ± 4.8%, p < 0.001). The administration of both atorvastatin and bosentan resulted in significantly higher collagen content and thicker fibrous cap versus COG (p < 0.01). All intervention groups showed lower relative intra-plaque concentrations of MCP-1, MMP-3, and MMP-9 and a higher TIMP-1concentration compared to COG (p < 0.001). Importantly, latter parameters presented lower levels when bosentan was combined with atorvastatin compared to COG (p < 0.05). Bosentan treatment in diabetic, atherosclerotic ApoE-/- mice delayed the atherosclerosis progression and enhanced plaques\' stability, showing modest but additive effects with atorvastatin, which are promising in atherosclerotic cardiovascular diseases.

Aneurysms pose life-threatening risks due to the dilatation of the arteries and carry a high risk of rupture. Despite continuous research efforts, there are still no satisfactory or clinically effective pharmaceutical treatments for this condition. Accelerated inflammatory processes during aneurysm development lead to increased levels of matrix metalloproteinases (MMPs) and destabilization of the vessel wall through the degradation of the structural components of the extracellular matrix (ECM), mainly collagen and elastin. Tissue inhibitors of metalloproteinases (TIMPs) directly regulate MMP activity and consequently inhibit ECM proteolysis. In this work, the synthesis of TIMP-1 protein was increased by the exogenous delivery of synthetic TIMP-1 encoding mRNA into aortic vessel tissue in an attempt to inhibit MMP-9. In vitro, TIMP-1 mRNA transfection resulted in significantly increased TIMP-1 protein expression in various cells. The functionality of the expressed protein was evaluated in an appropriate ex vivo aortic vessel model. Decreased MMP-9 activity was detected using in situ zymography 24 h and 48 h post microinjection of 5 µg TIMP-1 mRNA into the aortic vessel wall. These results suggest that TIMP-1 mRNA administration is a promising approach for the treatment of aneurysms.

Despite the significant changes that unfold during the subacute phase of stroke, few studies have examined recovery abilities during this critical period. As neuroinflammation subsides and tissue degradation diminishes, the processes of neuroplasticity and angiogenesis intensify. An important factor in brain physiology and pathology, particularly neuroplasticity, is matrix metalloproteinase 9 (MMP-9). Its activity is modulated by tissue inhibitors of metalloproteinases (TIMPs), which impede substrate binding and activity by binding to its active sites. Notably, TIMP-1 specifically targets MMP-9 among other matrix metalloproteinases (MMPs). Our present study examines whether MMP-9 may play a beneficial role in psychological functions, particularly in alleviating depressive symptoms and enhancing specific cognitive domains, such as calculation. It appears that improvements in depressive symptoms during rehabilitation were notably linked with baseline MMP-9 plasma levels (r = -0.36, p = 0.025), and particularly so with the ratio of MMP-9 to TIMP-1, indicative of active MMP-9 (r = -0.42, p = 0.008). Furthermore, our findings support previous research demonstrating an inverse relationship between pre-rehabilitation MMP-9 serum levels and post-rehabilitation motor function. Crucially, our study emphasizes a positive correlation between cognition and motor function, highlighting the necessity of integrating both aspects into rehabilitation planning. These findings demonstrate the potential utility of MMP-9 as a prognostic biomarker for delineating recovery trajectories and guiding personalized treatment strategies for stroke patients during the subacute phase.

This study investigated the diagnostic accuracy of plasma biomarkers-specifically, matrix metalloproteinase (MMP-9), tissue inhibitor of metalloproteinase (TIMP-1), CD147, and the MMP-/TIMP-1 ratio in patients with Alzheimer\'s disease (AD) dementia. The research cohort comprised patients diagnosed with probable AD dementia and a control group of cognitively unimpaired (CU) individuals. Neuroradiological assessments included brain magnetic resonance imaging (MRI) following dementia protocols, with subsequent volumetric analysis. Additionally, cerebrospinal fluid (CSF) AD biomarkers were classified using the A/T/N system, and apolipoprotein E (APOE) ε4 carrier status was determined. Findings revealed elevated plasma levels of MMP-9 and TIMP-1 in AD dementia patients compared to CU individuals. Receiver operating characteristic (ROC) curve analysis demonstrated significant differences in the areas under the curve (AUC) for MMP-9 (p < 0.001) and TIMP-1 (p < 0.001). Notably, plasma TIMP-1 levels were significantly lower in APOE ε4+ patients than in APOE ε4- patients (p = 0.041). Furthermore, APOE ε4+ patients exhibited reduced hippocampal volume, particularly in total, right, and left hippocampal measurements. TIMP-1 levels exhibited a positive correlation, while the MMP-9/TIMP-1 ratio showed a negative correlation with hippocampal volume parameters. This study sheds light on the potential use of TIMP-1 as a diagnostic marker and its association with hippocampal changes in AD.

BACKGROUND: Liver cirrhosis, a prevalent chronic liver disease, is characterized by liver fibrosis as its central pathological process. Recent advancements highlight the clinical efficacy of umbilical cord mesenchymal stem cell (UC-MSC) therapy in the treatment of liver cirrhosis.
RESULTS: We investigated the pharmacodynamic effects of UC-MSCs and MSC conditional medium (MSC-CM) in vivo, utilizing a carbon tetrachloride (CCl4)-induced fibrotic rat model. Concurrently, we assessed the in vitro impact of MSCs and MSC-CM on various cellular process of hepatic stellate cells (HSCs), including proliferation, apoptosis, activation, immunomodulatory capabilities, and inflammatory factor secretion. Our results indicate that both MSCs and MSC-CM significantly ameliorate the pathological extent of fibrosis in animal tissues, reducing the collagen content, serum biochemical indices and fibrosis biomarkers. In vitro, MSC-CM significantly inhibited the activation of the HSC line LX-2. Notably, MSC-CM modulated the expression of type I procollagen and TGFβ-1 while increasing MMP1 expression. This modulation restored the MMP1/TIMP1 ratio imbalance and extracellular matrix deposition in TGFβ-1 induced fibrosis. Both MSCs and MSC-CM not only induced apoptosis in HSCs but also suppressed proliferation and inflammatory cytokine release from activated HSCs. Furthermore, MSCs and MSC-CM exerted a suppressive effect on total lymphocyte activation.
CONCLUSIONS: UC-MSCs and MSC-CM primarily modulate liver fibrosis severity by regulating HSC activation. This study provides both in vivo and in vitro pharmacodynamic evidence supporting the use of MSCs in liver fibrosis treatment.

OBJECTIVE: The present study aims to investigate the specific protective effects and underlying mechanisms of Ganshuang granule (GSG) on dimethylnitrosamine (DMN)-induced hepatic fibrosis in rat models.
METHODS: Hepatic fibrosis was experimentally evoked in rats by DMN administration, and varying dosages of GSG were employed as an intervention. Hepatocellular damage was assessed by measuring serum levels of aminotransferase and bilirubin, accompanied by histopathological examinations of hepatic tissue. The hepatic concentrations of platelet-derived growth factor (PDGF) and transforming growth factor-β1 (TGF-β1) were quantitated via enzyme-linked immunosorbent assay (ELISA). The expression of α-smooth muscle actin (α-SMA) within hepatic tissue was evaluated using immunohistochemical techniques. The levels of hepatic interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), and a spectrum of interleukins (IL-2, IL-4, IL-6, IL-10) were quantified by quantitative real-time PCR (qRT-PCR). Additionally, hepatic stellate cells (HSCs) were cultured in vitro and exposed to TNF-α in the presence of naringin, a principal component of GSG. The gene expression levels of tissue inhibitor of metalloproteinase-1 (TIMP-1) and matrix metallopeptidase-1 (MMP-1) in these cells were also quantified by qRT-PCR. Proliferative activity of HSCs was evaluated by the Cell Counting Kit-8 assay. Finally, alterations in Smad protein expression were analyzed through Western blotting.
RESULTS: Administration of GSG in rats with fibrosis resulted in reduced levels of serum aminotransferases and bilirubin, along with alleviation of histopathological liver injury. Furthermore, the fibrosis rats treated with GSG exhibited significant downregulation of hepatic TGF-β1, PDGF, and TNF-α levels. Additionally, GSG treatment led to increased mRNA levels of IFN-γ, IL-2, and IL-4, as well as decreased expression of α-SMA in the liver. Furthermore, treatment with naringin, a pivotal extract of GSG, resulted in elevated expression of MMP-1 and decreased levels of TIMP-1 in TNF-α-stimulated HSCs when compared to the control group. Additionally, naringin administration led to a reduction in Smad expression within the HSCs.
CONCLUSIONS: GSG has the potential to mitigate fibrosis induced by DMN in rat models through the regulation of inflammatory and fibrosis factors. Notably, naringin, the primary extract of GSG, may exert a pivotal role in modulating the TGF-β-Smad signaling pathway.

OBJECTIVE: Cancer-associated fibroblasts (CAFs) have been shown to promote the metastasis of head and neck squamous cell carcinoma (HNSCC), but the underlying mechanisms remain unclear. The purpose of this study is to identify gene in CAFs that are associated with metastasis and to preliminarily validate its impact on the metastasis of HNSCC.
METHODS: Scissor analysis was utilized to process single-cell and bulk RNA sequencing datasets, identifying genes associated with the metastasis of HNSCC through differential gene expression analysis. A risk model was constructed using LASSO regression analysis. Quantitative real time-PCR and Western blot were employed to measure mRNA and protein expressions, respectively. Multiplex immunohistochemistry (mIHC) was used to assess protein expression in CAFs. siRNA was utilized to achieve gene knockdown. CCK-8 and Transwell assays were employed to evaluate the biological characteristics of HNSCC cells.
RESULTS: Compare to the nonmetastatic primary CAFs (nmCAFs), tissue inhibitors of metalloproteinase-1 (TIMP1) was founded to be overexpressed in the cells and tissues of metastatic primary CAFs (mCAFs). Knocking down TIMP1 in CAFs can signifucantly inhibit the proliferation, invasion, and migration of HNSCC cells.
CONCLUSIONS: CAFs facilitate HNSCC cell metastasis by upregulating TIMP1, highlighting TIMP1 as a potential therapeutic target in HNSCC metastasis management.

To explore the molecular pathogenesis of pulmonary arterial hypertension (PAH) and identify potential therapeutic targets, we performed transcriptome sequencing of lung tissue from mice with hypoxia-induced pulmonary hypertension. Our Gene Ontology analysis revealed that \"extracellular matrix organization\" ranked high in the biological process category, and matrix metallopeptidases (MMPs) and other proteases also played important roles in it. Moreover, compared with those in the normoxia group, we confirmed that MMPs expression was upregulated in the hypoxia group, while the hub gene Timp1 was downregulated. Crocin, a natural MMP inhibitor, was found to reduce inflammation, decrease MMPs levels, increase Timp1 expression levels, and attenuate hypoxia-induced pulmonary hypertension in mice. In addition, analysis of the cell distribution of MMPs and Timp1 in the human lung cell atlas using single-cell RNAseq datasets revealed that MMPs and Timp1 are mainly expressed in a population of fibroblasts. Moreover, in vitro experiments revealed that crocin significantly inhibited myofibroblast proliferation, migration, and extracellular matrix deposition. Furthermore, we demonstrated that crocin inhibited TGF-β1-induced fibroblast activation and regulated the pulmonary arterial fibroblast MMP2/TIMP1 balance by inhibiting the TGF-β1/Smad3 signaling pathway. In summary, our results indicate that crocin attenuates hypoxia-induced pulmonary hypertension in mice by inhibiting TGF-β1-induced myofibroblast activation.