Cyclophilins A, B, and C Role in Human T Lymphocytes Upon Inflammatory Conditions

Promoting activities of human cyclophilin A on calcium oxalate stone formation at crystal growth, aggregation and crystal-cell adhesion phases

Kidney stone is a specialized form of biomineralization involving complex interactions between crystals and urinary macromolecules. Renal tubular cells secrete cyclophilin A (CyPA), a protein whose elevated level is associated with various kidney diseases. Nevertheless, its role in kidney stone formation has not previously been explored. This study thus aimed to investigate roles of CyPA in kidney stone formation through various calcium oxalate (CaOx) crystal assays. Recombinant human CyPA was generated to mimic its secretory form excreted into the urine. Crystal assays yielded the first evidence demonstrating that CyPA significantly promoted CaOx growth, aggregation and crystal-cell adhesion, all of which are the critical steps during initial CaOx stone formation. Despite the lack of specific Ca2+-binding and Ox2--binding domains and its inability to bind free Ca2+/Ox2- ions in solution, CyPA demonstrated a distinct ability to bind CaOx crystals. Upon binding, CyPA facilitated further CaOx growth, aggregation of adjacent crystals and crystal-cell adhesion. These findings unravel a novel mechanism of kidney stone pathogenesis, expanding the known functions of CyPA. This research also provides solid evidence of how CyPA became one of the compositions in the stone matrix and highlights its potential to be a therapeutic/preventive target for management/prevention of kidney stone disease.

Cyclophilin A and C are the Main Components of Extracellular Vesicles in Response to Hyperglycemia in BV2 Microglial Cells

Cyclophilins (Cyps) and CD147 receptor play a crucial role in the inflammatory responses. Chronic inflammation causes tissue damage and is a common condition of several inflammation-based pathologies as diabetes or Alzheimer´s disease. Under high glucose (HG) conditions, microglia is activated and releases inflammatory mediators. In this process the role of Cyps is unknown, so this study was aimed to investigate the profile of Cyps in microglia and their release through extracellular vesicles (EVs) under hyperglycemia. An increase in reactive oxygen species (ROS) and nitric oxide (NO) levels was observed when BV2 glia cells were incubated with HG concentration. These effects were mitigated by the Cyps inhibitor cyclosporine A (CsA), suggesting the implication of Cyps in BV2 activation. In these conditions the intracellular expression of CypA, B, C and D, as well as the membrane expression of CD147 receptor was increased. In addition, only CypA and CypC were detected in the extracellular medium. Then, the presence of Cyps inside EVs was explored as an alternative secretion route. Interestingly, under HG treatment, an increase in the levels of the four Cyps in EVs was observed. When neurons were treated with EVs derived from HG-treated glia cells, their viability was reduced and EVs were detected in cytosol neurons pointing to an EVs-Cyps neurotoxic effect. These findings provide novel insights into the relationship between Cyps and EVs in neuroinflammation in hyperglycemia conditions. The current results strengthen the role of Cyps in cell communication and its potential role in brain function under pathological conditions.

Serum Angptl2 and CyPA Levels in Acute Myocardial Infarction and In-Stent Restenosis After Percutaneous Coronary Intervention: A Single-Center Retrospective Case-Control Study

Purpose

To explore the association between angiopoietin-like protein 2 (Angptl2) and cyclophilin A (CyPA) with acute myocardial infarction (AMI) and the occurrence of in-stent restenosis (ISR) after percutaneous coronary intervention (PCI).

Patients and Methods

A single-center retrospective research was conducted. Clinical data from 146 AMI patients who underwent PCI at our hospital were analyzed and designated as the AMI group. Additionally, 56 healthy individuals who underwent medical check-ups during the same period were enrolled as the Control group. Serum levels of Angptl2 and CyPA were compared between the AMI and control groups. Furthermore, based on the presence or absence of in-stent restenosis (ISR) during the follow-up period, the AMI patients were further divided into ISR and NISR groups. Logistic regression analysis was utilized to ascertain the risk factors influencing ISR after PCI in AMI patients. The diagnostic value of serum Angptl2 and CyPA for ISR after PCI was assessed using the receiver operating characteristic (ROC) curve.

Results

Compared with the Control group, the AMI group exhibited significantly elevated levels of Angptl2 and CyPA (P<0.05). Logistic regression analysis identified serum Angptl2 and CyPA are risk factors for occurrence of ISR after PCI in AMI patients. Additionally, the ROC curve analysis demonstrated that the combined use of serum Angptl2 and CyPA achieved an area under the curve (AUC) of 0.895 for predicting ISR in AMI patients after PCI.

Conclusion

Elevated serum levels of Angptl2 and CyPA in AMI patients who developed ISR after PCI suggest that these biomarkers may serve as potential risk indicators for predicting ISR following PCI.

Explosive cytotoxicity of 'ruptoblasts' bridges hormonal surveillance and immune defense

Cytotoxic killing is an essential immune function, yet its cellular mechanisms have been characterized in only a few model species. Here, we show that planarian flatworms harness a unique cytotoxic strategy. In planarians, activin, a hormone regulating regeneration and reproduction, also acts as an inflammatory cytokine. Overactivation of activin signaling - through protein injection, genetic chimerism, or bacterial infection - triggers 'ruptoblasts', an undocumented immune cell type, to undergo 'ruptosis', a unique mode of cell bursting that eliminates nearby cells and bacteria in mere minutes, representing one of the fastest cytotoxic mechanisms observed. Ablating ruptoblasts suppresses inflammation but compromises bacterial clearance, highlighting ruptoblasts' broad-spectrum immune functions. We further identified ruptoblast-like cells in diverse basal bilaterians, unveiling an alternative strategy that couples hormonal regulation with immune defense and expanding the landscape of evolutionary immune innovations.

Basigin in cerebrovascular diseases: Roles, mechanisms, and therapeutic target potential

Cerebrovascular diseases are major global health issues, responsible for significant morbidity and mortality. Basigin (additionally called CD147 or EMMPRIN) is a glycosylated transmembrane protein that facilitates intercellular communication. Recent research has highlighted the critical role of Basigin in inducing matrix metalloproteinases (MMPs), which contribute to the progression of cerebrovascular diseases. Consequently, Basigin has emerged as a promising therapeutic target for these conditions. However, inhibiting the pivotal role of Basigin in mediating cerebrovascular disease is an urgent area of investigation. In this review, we systematically examine the pathological mechanisms by which Basigin contributes to the development of cerebrovascular diseases. We present evidence demonstrating the protective effect of targeted inhibition of Basigin in these conditions and suggest future research directions.

PPIH is a novel diagnostic biomarker associated with immune infiltration in cholangiocarcinoma

BACKGROUND

Cholangiocarcinoma (CHOL) is the second most common primary liver malignancy, characterized by high aggressiveness and heterogeneity. It is typically diagnosed at an advanced stage, leading to a poor prognosis. Although Peptidyl Proline Isomerase H (PPIH) has been implicated in various tumors, its role in CHOL remains unexplored. This study aims to investigate the diagnostic value and potential function of PPIH in CHOL.

METHODS

We analyzed the expression levels, prognostic significance, and diagnostic efficiency of PPIH in CHOL using data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) datasets, coupled with gene enrichment analyses. The CIBERSORT database was employed to assess the correlation between PPIH expression and immune cell infiltration in CHOL. Additionally, immunohistochemical experiments were conducted to validate PPIH expression levels in CHOL tissues and to explore its correlation with TP53 gene mutations.

RESULTS

Our findings indicate that overexpression of PPIH mRNA in CHOL is associated with poor prognosis, with increased PPIH protein levels observed in CHOL tissues. Furthermore, PPIH expression showed a positive correlation with TP53 mutations. PPIH demonstrated strong diagnostic value for CHOL. Moreover, PPIH may influence tumor progression through its involvement in cell cycle regulation and spliceosome pathways, and is associated with immune cell infiltration levels.

CONCLUSION

The results of this study suggest that PPIH is a potential novel biomarker with significant diagnostic value for patients with CHOL. PPIH may also play a role in modulating the immune microenvironment, contributing to poor prognosis.

Broad-spectrum antiviral strategy: Host-targeting antivirals against emerging and re-emerging viruses

Viral infections are amongst the most prevalent diseases that pose a significant threat to human health. Targeting viral proteins or host factors represents two primary strategies for the development of antiviral drugs. In contrast to virus-targeting antivirals (VTAs), host-targeting antivirals (HTAs) offer advantages in terms of overcoming drug resistance and effectively combating a wide range of viruses, including newly emerging ones. Therefore, targeting host factors emerges as an extremely promising strategy with the potential to address critical challenges faced by VTAs. In recent years, extensive research has been conducted on the discovery and development of HTAs, leading to the approval of maraviroc, a chemokine receptor type 5 (CCR5) antagonist used for the treatment of HIV-1 infected individuals, with several other potential treatments in various stages of development for different viral infections. This review systematically summarizes advancements made in medicinal chemistry regarding various host targets and classifies them into four distinct catagories based on their involvement in the viral life cycle: virus attachment and entry, biosynthesis, nuclear import and export, and viral release.

Structural Insights into SARS-CoV-2 Nonstructural Protein 1 Interaction with Human Cyclophilin and FKBP1 to Regulate Interferon Production

The ongoing coronavirus disease 2019 (COVID-19) pandemic caused by the SARS-CoV-2 coronavirus and the perpetual rise of new variants warrant investigation of the molecular and structural details of the infection process and modulation of the host defense by viral proteins. This Letter reports the combined experimental and computational approaches to provide key insights into the structural and functional basis of Nsp1's association with different cyclophilins and FKBPs in regulating COVID-19 infection. We demonstrated the real-time stability and functional dynamics of the Nsp1-CypA/FKBP1A complex and investigated the repurposing of potential inhibitors that could block these interactions. Overall, we provided insights into the inhibitory role Nsp1 in downstream interferon production, a key aspect for host defense that prevents the SARS-CoV-2 or related family of corona virus infection.

Endoplasmic Reticulum Stress and Its Impact on Adipogenesis: Molecular Mechanisms Implicated

Endoplasmic reticulum (ER) stress plays a pivotal role in adipogenesis, which encompasses the differentiation of adipocytes and lipid accumulation. Sustained ER stress has the potential to disrupt the signaling of the unfolded protein response (UPR), thereby influencing adipogenesis. This comprehensive review illuminates the molecular mechanisms that underpin the interplay between ER stress and adipogenesis. We delve into the dysregulation of UPR pathways, namely, IRE1-XBP1, PERK and ATF6 in relation to adipocyte differentiation, lipid metabolism, and tissue inflammation. Moreover, we scrutinize how ER stress impacts key adipogenic transcription factors such as proliferator-activated receptor γ (PPARγ) and CCAAT-enhancer-binding proteins (C/EBPs) along with their interaction with other signaling pathways. The cellular ramifications include alterations in lipid metabolism, dysregulation of adipokines, and aged adipose tissue inflammation. We also discuss the potential roles the molecular chaperones cyclophilin A and cyclophilin B play in adipogenesis. By shedding light on the intricate relationship between ER stress and adipogenesis, this review paves the way for devising innovative therapeutic interventions.

PPIH gene regulation system and its prognostic significance in hepatocellular carcinoma: a comprehensive analysis

BACKGROUND

Peptidyl-prolyl isomerase H (PPIH) is a member of the cyclophilin protein family, which functions as a molecular chaperone and is involved in the splicing of pre-mRNA. According to reports, the malignant progression of HCC related to hepatitis B virus (HBV) is tightly associated with RNA-binding proteins. Nevertheless, there is no research on PPIH expression or its function in the occurrence and progression of HCC.

RESULTS

We are the first to reveal that the mRNA and protein levels of Ppih are substantially overexpressed in HCC, as the outcomes show. A significant correlation existed between enriched expression of Ppih within HCC and more advanced, poorly differentiated, and TP53-mutated tumors.

CONCLUSION

These findings, which suggest that Ppih may serve as a predictive biomarker for people with HCC, serve as a starting point for further investigation into the function of Ppih in the progression of carcinogenesis.

METHODS

Accordingly, we utilized clinical samples and bioinformatics analysis to assess Ppih's mRNA, protein expression, and gene regulatory system in HCC. Additionally, Wilcoxon signed-rank testing and logistic regression were utilized to inspect the association between clinicopathological factors and Ppih. Clinical pathological traits linked to overall survival (OS) among HCC patients were examined via TCGA data via Cox regression and the Kaplan-Meier approach. Additionally, via TCGA data collection, gene set enrichment assessment was also conducted.

Testosterone upregulates glial cell line-derived neurotrophic factor (GDNF) and promotes neuroinflammation to enhance glioma cell survival and proliferation

BACKGROUND

Testosterone contributes to male organism development, such as bone density, muscle development, and fat repartition. Estrogen (derived from testosterone) also contributes to female reproductive system development. Here, we investigated the effect of testosterone on glioma cells and brain neuron inflammation essential for cancer development and progression.

METHODS

The human astrocyte and glioma cell lines were treated with 6 ng/ml exogenous testosterone in vitro. We performed cell counting kit-8, transwell, and wound healing assays to determine the effect of testosterone on glioma cell proliferation, migration, and invasion. The glioma cells were injected into the xenograft and treated with 5 µl concentrated testosterone. Transcriptional suppression of glial cell line-derived neurotrophic factor (GDNF) was performed to evaluate brain neuron inflammation and survival. The tumor tissues were assessed by hematoxylin-eosin staining and immunohistochemistry.

RESULTS

Testosterone upregulates GDNF to stimulate proliferation, migration, and invasion of glioma cells. Pathologically, the augmentation of GDNF and cyclophilin A contributed to neuroprotection when treated with testosterone. Our investigation showed that testosterone contributes to brain neuron and astrocyte inflammation through the upregulation of nuclear factor erythroid 2-related factor 2 (NRF2), glial fibrillary acid protein (GFAP), and sirtuin 5 (SIRT5), resulting in pro-inflammatory macrophages recruitments into the neural microenvironment. Mechanically, testosterone treatment regulates GDNF translocation from the glioma cells and astrocyte nuclei to the cytoplasm.

CONCLUSION

Testosterone upregulates GDNF in glioma cells and astrocytes essential for microglial proliferation, migration, and invasion. Testosterone contributes to brain tumor growth via GDNF and inflammation. The contribution of testosterone, macrophages, and astrocytes, in old neuron rescue, survival, and proliferation. During brain neuron inflammation, the organism activates and stimulates the neuron rescue through the enrichment of the old neuron microenvironment with growth factors such as GDNF, BDNF, SOX1/2, and MAPK secreted by the surrounding neurons and glial cells to maintain the damaged neuron by inflammation alive even if the axon is dead. The immune response also contributes to brain cell survival through the secretion of proinflammatory cytokines, resulting in inflammation maintenance. The rescued old neuron interaction with infiltrated macrophages contributes to angiogenesis to supplement the old neuron with more nutrients leading to metabolism activation and surrounding cell uncontrollable cell growth.

On the human health benefits of microalgal phytohormones: An explorative in silico analysis

Phytohormones represent a group of secondary metabolites with different chemical structures, in which belong auxins, cytokinins, gibberellins, or brassinosteroids. In higher plants, they cover active roles in growth or defense function, while their potential benefits for human health protection were noted for some phytohormones and little explored for many others. In this study, we developed a target fishing strategy on fifty-three selected naturally occurring phytohormones covering different families towards proteins involved in key cellular functions related to human metabolism and health protection/disease. This in silico analysis strategy aims to screen the potential human health-driven bioactivity of more than fifty phytohormones through the analysis of their interactions with specific targets. From this analysis, twenty-eight human targets were recovered. Some targets e.g., the proteins mitochondrial glutamate dehydrogenase (GLUD1) or nerve growth factor (NGF) bound many phytohormones, highlighting their involvement in amino acid metabolism and/or in the maintenance or survival of neurons. Conversely, some phytohormones specifically interacted with some proteins, e.g., SPRY domain-containing SOCS box protein 2 (SPSB2) or Inosine-5'-monophosphate dehydrogenase 1 (IMPDH1), both involved in human immune response. They were then investigated with a molecular docking analysis approach. Our bioprospecting study indicated that many phytohormones may endow human health benefits, with potential functional role in multiple cellular processes including immune response and cell cycle progression.

Extracellular cyclophilins A and C induce dysfunction of pancreatic microendothelial cells

Extracellular cyclophilins (eCyps) A and B are chemotactic mediators in several illnesses in which inflammation plays an important role such as diabetes and cardiovascular diseases. Recently, eCypC has been reported as a potential biomarker for coronary artery disease but its effect in endothelium has not been determined. Moreover, there is a lack of studies with all these proteins in the same model, which makes difficult a direct comparison of their effects. In this work, MS1 pancreatic microendothelial cells were treated with eCyps A, B and C and their impact on endothelial function was analysed. eCyps A and C stimulated the release of IL-6 and MCP-1 and increased the expression of the receptor CD147, but eCypB did not affect these pro-inflammatory markers. Moreover, eCypC activated the translocation of NFkB-p65 to the nucleus. All these effects were reversed by pre-treatment with cyclosporine A. eCyps also produced endothelial dysfunction, as evidenced by the decrease in eNOS activation. Finally, the crosstalk among eCyps addition and their protein and gene expression was evaluated. eCypA generated a depletion in its protein and gene levels, whilst eCyps B and C upregulated their own protein expression. Moreover, each eCyp altered the intracellular expression of other Cyps, including cyclophilin D. This work is the first report of eCyps influence on iCyps expression, as well as the first description of eCypC as an activator of CD147 receptor and a mediator of endothelial dysfunction, which points to a potential role of this protein in vascular complications associated to diabetes.

Role of MMP-2 and CD147 in kidney fibrosis

Matrix metalloproteinase-2 (MMP-2) and cluster of differentiation 147 (CD147) both play important roles in the development of kidney fibrosis, and CD147 can induce the production and activation of MMP-2. In the early stage of kidney fibrosis, MMP-2 promotes extracellular matrix (ECM) production and accelerates the development of kidney fibrosis, while in the advanced stage, MMP-2 activity decreases, leading to reduced ECM degradation and making it difficult to alleviate kidney fibrosis. The reason for the decrease in MMP-2 activity in the advanced stage is still unclear. On the one hand, it may be related to hypoxia and endocytosis, which lead to changes in the expression of MMP-2-related active regulatory molecules; on the other hand, it may be related to insufficient CD147 function. At present, the specific process by which CD147 is involved in the regulation of MMP-2 activity is not completely clear, and further in-depth studies are needed to clarify the roles of both factors in the pathophysiology of kidney fibrosis.

Furanoditerpenes from Spongia (Spongia) tubulifera Display Mitochondrial-Mediated Neuroprotective Effects by Targeting Cyclophilin D

Neuroprotective properties of five previously described furanoditerpenes 1-5, isolated from Spongia (Spongia) tubulifera, were evaluated in an in vitro oxidative stress model in SH-SY5Y cells. Dose-response treatments revealed that 1-5 improved cell survival at nanomolar concentrations through the restoration of mitochondrial membrane potential and the reduction of reactive oxygen species. Their ability to prevent the mitochondrial permeability transition pore opening was also assessed, finding that 4 and 5 inhibited the channel at 0.001 μM. This inhibition was accompanied by a decrease in the expression of cyclophilin D, the main regulator of the pore, which was also reduced by 1 and 2. However, the activation of ERK and GSK3β, upstream modulators of the channel, was not affected by compounds. Therefore, their ability to bind cyclophilin D was evaluated by surface plasmon resonance, observing that 2-5 presented equilibrium dissociation constants in the micromolar range. All compounds also showed affinity for cyclophilin A, being 1 selective toward this isoform, while 2 and 5 exhibited selectivity for cyclophilin D. When the effects on the intracellular expression of cyclophilins A-C were determined, it was found that only 1 decreased cyclophilin A, while cyclophilins B and C were diminished by most compounds, displaying enhanced effects under oxidative stress conditions. Results indicate that furanoditerpenes 1-5 have mitochondrial-mediated neuroprotective properties through direct interaction with cyclophilin D. Due to the important role of this protein in oxidative stress and inflammation, compounds are promising drugs for new therapeutic strategies against neurodegeneration.

The Multiple Roles of CD147 in the Development and Progression of Oral Squamous Cell Carcinoma: An Overview

Cluster of differentiation (CD)147, also termed extracellular matrix metalloprotease inducer or basigin, is a glycoprotein ubiquitously expressed throughout the human body, the oral cavity included. CD147 actively participates in physiological tissue development or growth and has important roles in reactive processes such as inflammation, immunity, and tissue repair. It is worth noting that deregulated expression and/or activity of CD147 is observed in chronic inflammatory or degenerative diseases, as well as in neoplasms. Among the latter, oral squamous cell carcinoma (OSCC) is characterized by an upregulation of CD147 in both the neoplastic and normal cells constituting the tumor mass. Most interestingly, the expression and/or activity of CD147 gradually increase as healthy oral mucosa becomes inflamed; hyperplastic/dysplastic lesions are then set on, and, eventually, OSCC develops. Based on these findings, here we summarize published studies which evaluate whether CD147 could be employed as a marker to monitor OSCC development and progression. Moreover, we describe CD147-promoted cellular and molecular events which are relevant to oral carcinogenesis, with the aim to provide useful information for assessing whether CD147 may be the target of novel therapeutic approaches directed against OSCC.

Anhydroexfoliamycin, a Streptomyces Secondary Metabolite, Mitigates Microglia-Driven Inflammation

Anhydroexfoliamycin, a secondary metabolite from Streptomyces, has shown antioxidant properties in primary cortical neurons reducing neurodegenerative hallmarks diseases, both in vitro and in vivo models. Activated microglia, in the central nervous system, plays a crucial role in neuroinflammation and is associated with neurodegeneration. Therefore, the aim of the present study was to determine the anti-inflammatory and antioxidant potential of the anhydroexfoliamycin over microglia BV2 cells. Neuroinflammation was simulated by incubation of microglia cells in the presence of lipopolysaccharide to activate proinflammatory transduction pathways. Moreover, a coculture of neuron SH-SY5Y and microglia BV2 cells was used to evaluate the neuroprotective properties of the Streptomyces metabolite. When microglia cells were preincubated with anhydroexfoliamycin, proinflammatory pathways, such as the translocation of the nuclear factor κB, the phosphorylation of c-Jun N-terminal kinase, and the inducible nitric oxide synthase expression, were inhibited. In addition, intracellular reactive oxygen species generation and the liberation of nitric oxide, interleukin 6, and tumor necrosis factor α were also decreased. Besides, the Streptomyces-derived compound showed antioxidant properties promoting the translocation of the factor erythroid 2-related factor 2 and protecting the SH-SY5Y cells from the neurotoxic mediators released by activated microglia. The effects of this compound were at the same level as the immunosuppressive drug cyclosporine A. Therefore, these results indicate that anhydroexfoliamycin is a promising tool to control microglia-driven inflammation with therapeutic potential in neuroinflammation.