Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie最新文献

Parkinson's disease (PD) is a neurological disorder that causes a gradual decrease in mobility. Abnormal α-synuclein (α-syn) levels and aggregation contribute to PD development. The dissemination of α-synuclein pathology via the gut-brain axis has emerged as a critical aspect in α-synucleinopathies, including PD. Recently, α7 nicotinic acetylcholine receptor (α7nAchR) agonists have been proposed as promising agents for treating PD, owing to their biological properties such as anti-inflammatory effects. This study aims to investigate whether activation of α7nAchR improves α-synuclein pathology in the brain and gut of a mouse model of PD. We found that α7nAchR agonists, GTS-21 and PNU-282987, induced behavioral recovery and improved nigrostriatal dopaminergic neurotransmission in a subacute MPTP mouse model of PD. In addition, GTS-21 and PNU-282987 facilitated α-syn clearance in the brain and distal colon, as evidenced by a considerable reduction in the accumulation of pathogenic forms of α-syn. Accordingly, GTS-21 and PNU-282987 were found to promote the AMPK-mTOR autophagy signaling pathway. Furthermore, GTS-21 and PNU-282987 exerted anti-inflammatory effects, reducing the levels of proinflammatory mediators such as inducible nitric oxide synthase, interleukin-6, and tumor necrosis factor-α in both the brain and gut. To validate the specific effects of α7nAchR agonists, subacute MPTP mice were pretreated with methyllycaconitine (MLA), a selective α7nAchR antagonist before GTS-21 administration. Pretreatment with MLA abolished the GTS-21-elicited behavioral recovery, α-syn clearance, and anti-inflammatory effects in the brain and gut. Therefore, α7nAchR activation may be a potential candidate strategy for the treatment of PD by altering α-syn aggregation in the brain and gut.

In colitis-associated colorectal cancer (CAC), the NF-κB pathway, especially IKKβ, drives inflammation and cancer progression. However, no IKKβ inhibitors have been approved due to compensatory mechanisms. The challenge is to develop an anti-tumor agent that effectively targets IKKβ while overcoming these compensatory pathways. We conducted in vitro and in vivo experiments to evaluate the anti-cancer effects of synthesized xanthohumol (XN) targeting IKKβ. CAC was induced in mice, followed by XN treatment. Histological and molecular analyses, including cell viability assays, immunoblotting, and qRT-PCR, were performed. Human colon cancer cell lines were also used to investigate IKKβ's role. RNA sequencing revealed elevated IKKβ expression in colorectal cancer human tissues, correlating with poor prognosis. XN significantly reduced adenocarcinoma formation and inflammation in vivo while decreasing IKKβ and NF-κB signaling in both models. XN binds to the C179 residue of IKKβ, inhibiting its activity. Additionally, our findings highlight KEAP1's role as an upstream regulator of IKKβ degradation. XN specifically interacts with the C288 residue of KEAP1, showing triple-binding affinity with IKKβ and KEAP1. These results indicate that XN promotes conditions where KEAP1 facilitates IKKβ degradation.

Multiple myeloma (MM) is an incurable plasma cell malignancy characterized by frequent relapse due to acquired treatment resistance, underscoring the need for innovative therapies, particularly for relapsed cases. This study explores the effects of low-dose bortezomib (BTZ) on programmed death ligand 1 (PD-L1) expression in MM cell lines and its potential to enhance T cell-mediated anti-tumor responses. Utilizing this PD-L1 upregulation, we employed bispecific αPD-L1 × αCD3 T cell engager-armed T cells (BATs) to block PD-L1 signaling and activate T cells. Flow cytometry confirmed that BATs selectively bound CD3 on T cells and PD-L1 on cancer cells, inducing T cell activation and proliferation without directly affecting cancer cell viability. BATs' cytotoxic activity was evaluated in MM cell lines with or without BTZ-induced PD-L1 expression. While KMS-12-PE cells showed no significant response, BATs significantly increased cell death in L363 cells, with further enhancement by BTZ. In RPMI-8226 cells, BATs demonstrated robust cytotoxicity, further amplified by BTZ. These results suggest that BATs, particularly in combination with BTZ, represent a promising strategy for treating MM, including bortezomib-resistant cases.

Pulmonary hypertension associated with bronchopulmonary dysplasia (BPD-PH) is a severe cardiorespiratory disease of preterm newborns leading to an excess of mortality in infancy and no curative treatment currently exists. Inflammation and oxidative stress are the common pathways that lead to BPD-PH. Therefore, we aimed to evaluate celastrol, a molecule with anti-inflammatory and antioxidant properties, as a promising preventive treatment in BPD-PH. In a model of neonatal rats exposed to hyperoxia, we demonstrated that mortality was prevented in animals treated with celastrol. Moreover, in vivo, celastrol decreased pulmonary hypertension, right ventricular hypertrophy, vascular remodeling, pulmonary arterial hyperreactivity to endothelin-1 and inflammation but had no effect on hypoalveolarization and altered angiogenesis. In vitro experiments carried out on human fetal pulmonary artery smooth muscle cells (HfPA-SMC) exposed to hyperoxia showed that endothelin-1-induced intracellular calcium response was increased and celastrol significantly inhibited this effect, without modifying endothelin-1 receptors expression. Regarding inflammation, celastrol decreased both CD68 staining in lung and secretion of the pro-inflammatory cytokine Tissue Inhibitor of Metalloproteinases-1 in intrapulmonary arteries from neonatal rats. IL-6 secretion was also decreased by celastrol in HfPA-SMC. Finally, hyperoxia increased heme oxygenase-1 (HO-1) expression and celastrol induced an overexpression of HO-1 in both neonatal rat lung and human cells. These results suggest that celastrol has a preventive effect on major hallmarks of PH in both a rat hyperoxic model of BPD-PH and HfPA-SMC exposed to hyperoxia via modulation of macrophage inflammatory signaling and HfPA-SMC calcium cycling. Celastrol could therefore be considered as a promising preventive treatment in BPD-PH.

The broad use of oligonucleotides (ON) in therapeutic and biotechnological applications is limited due to inefficient delivery methods. In parallel with lipids and polymeric carriers, cell-penetrating peptides (CPPs) are efficient vehicles for delivering nucleic acids of various types and activity into cells. In the current work, we examined the structural motifs required for the high efficacy of PepFect14, an often-used CPP for ON delivery, by introducing point mutations into the peptide sequence. We predicted the characteristics of modified CPPs, and analyzed their structure and ability to condense ONs into nanoparticles (NPs) using biophysical methods. We evaluated the ability of new PF14 analogs to deliver splicing switching oligonucleotides (SCO) and small interfering RNA (siRNA) in reporter cell lines, as well as microRNA miR-146a in human primary keratinocytes and in a mouse skin inflammation in vivo. Our findings indicate that the α-helical structure of PF14 is essential for efficient ON delivery, and mutations that disrupt the hydrophobic or cationic face in the peptide abolish NP formation and cellular internalization. PF14-Lys, an analog containing lysine residues instead of original ornithines, yielded a higher biological response to SCO and siRNA in the respective reporter cells than PF14. Furthermore, PF14-Lys efficiently delivered miRNA into keratinocytes and led to the subsequent downregulation of the target genes. Importantly, subcutaneously administered PF14-Lys-miR-146a NPs suppressed the inflammatory responses in mouse model of irritant contact dermatitis. In conclusion, our results suggest that PF14-Lys is a highly promising delivery vector for various oligonucleotides, applicable both in vitro and in vivo.

Treatment of heart failure and reduced ejection fraction (HFrEF) using angiotensin receptor-neprilysin inhibitor demonstrates beneficial effects on cardiac remodeling (CR). We assessed the impact of sacubitril/valsartan on the concentrations of HF biomarkers in relation to parameters of CR using imaging techniques in patients with HFrEF. In a prospective single-center open-label study, 68 patients with symptomatic HFrEF were treated with sacubitril/valsartan and followed-up every three months for 12 months. Soluble suppression of tumorigenicity 2 (sST2), N-terminal pro-B-type natriuretic peptide (NT-proBNP), and high-sensitivity cardiac troponin I (hs-cTnI) were measured in blood samples. Additionally, echocardiography and cardiac magnetic resonance imaging (cMRI) were performed to assess heart structural and functional changes. Following treatment initiation, follow-up visits revealed an improved NYHA functional class in these patients, alongside significant decreases in all circulating biomarkers, increases in left ventricular ejection fraction (LVEF), and reductions in volume- and diameter-related LV parameters. Sustained gradual decreases in sST2 concentrations over time correlated with NT-proBNP concentrations (rho=+0.26, P < 0.001). Both biomarkers were inversely correlated with LVEF, and positively correlated with volume- and diameter-related LV parameters from echocardiography and cMRI. However, NT-proBNP concentrations exhibited stronger correlations with these LV parameters and were associated with the number of LV segments showing fibrosis, unlike sST2. Sacubitril/valsartan treatment in HFrEF leads to reduced sST2 and NT-proBNP concentrations with distinct decreasing curves, which are linked to reverse CR through LV-related parameters. In contrast to sST2, NT-proBNP is also associated with fibrosis, suggesting that both biomarkers unveil distinct mechanisms during CR in patients treated with sacubitril/valsartan.

Abdominal aortic aneurysm (AAA) is a prevalent degenerative disease characterized by an exacerbated inflammation and destructive vascular remodeling. Unfortunately, effective pharmacological tools for the treatment of this disease remain a challenge. ATP-citrate lyase (ACLY), the primary enzyme responsible for acetyl-CoA biosynthesis, is a key regulator of inflammatory signaling in macrophages and lymphocytes. Here, we found increased levels of the active (phosphorylated) form of ACLY (p-ACLY) in the inflammatory infiltrate of AAA from patients and in aneurysmal lesions from angiotensin II (Ang II)-infused apolipoprotein E-deficient mice (ApoE^-/-). Furthermore, plasma ACLY levels positively correlates with IL6 and IFNγ levels in patients with AAA, while inflammatory stimuli strongly upregulated ACLY expression in macrophages and Jurkat cells. The administration of the ACLY inhibitor bempedoic acid (BemA) protected against Ang II-induced AAA formation in ApoE^-/- mice, limiting the progression of aortic dilatation and reducing mortality due to aortic rupture. BMS-303141, another ACLY inhibitor, also ameliorated AAA formation, although to a lesser extent. BemA attenuated vascular remodeling and the disorganization and rupture of elastic fibers induced by Ang II, as well as vascular inflammation, decreasing the recruitment of macrophages (CD68 +) and neutrophils (Ly-6G+) into the aortic wall. Moreover, BemA shifted splenic monocytes toward a functionally anti-inflammatory phenotype, and increased the percentage of CD4⁺CD69⁺ cells. Taken together, these results support the contribution of ACLY to AAA and point to BemA as a promising tool to be considered for future clinical trials addressing the management of this disease which is quite often associated with disorders of lipoprotein metabolism.

Drug resistance is a major cause of tumor mortality. Signaling networks became useful tools for driving pharmacological interventions against cancer drug resistance. Signaling datasets now cover the entire human cell. Recently, network adaptation became understood as a learning process. We review rapidly increasing evidence showing that the development of cancer drug resistance can be described as learning of signaling networks. During drug adaptation, the network forgets drug-affected pathways by desensitization and relearns by strengthening alternative pathways. Thus, resistant cancer cells develop a drug resistance memory. We show that all key players of cellular learning (i.e., IDPs, protein translocation, microRNAs/lncRNAs, scaffolding proteins and epigenetic/chromatin memory) have important roles in the development of cancer drug resistance. Moreover, all of them are central components of the epithelial-mesenchymal transition leading to metastases and resistance. Phenotypic plasticity was recently listed as a hallmark of cancer. We review how network plasticity induces rare, pre-existent drug-resistant cells in the absence of drug treatment. Key network methods assessing the development of drug resistance and network pharmacological interventions against drug resistance are summarized. Finally, we highlight the class of cellular memory drugs affecting cellular learning and forgetting, and we summarize current challenges to prevent or break drug resistance using network models.

Frostbite injury refers to cold tissue injury which typically affects the peripheral areas of the body, and is associated with limb loss and high rates of morbidity. Historically, treatment options have been limited to supportive care, leading to suboptimal outcomes for affected patients. The pathophysiology of frostbite injury has been understood in recent years to share similarity with that of cold ischemia-reperfusion injury as seen in solid organ transplantation, of which mitochondria play an important contributing role. The present study investigated whether AP39, a novel mitochondria-targeted slow-releasing hydrogen sulfide donor, applied topically in a vehicle cream at 200 nM or 1 µM could mitigate frostbite injury and promote wound healing in mice. Frostbite injury was induced continuously for 3 min on the dorsal skin of C57BL/6 mice (Mus musculus) using magnets frozen on dry ice (-80 °C). AP39, delivered via a vehicle cream, was used daily to treat frostbite injury until animals were euthanized on day 15 after induction of frostbite injury. Wound tissues were stained with hematoxylin and eosin along with immunofluorescence staining with cleaved caspase-3, CD31, KI-67, CD163, fibronectin and cytokeratin. While 200 nM AP39 improved granulation tissue maturation (p < 0.001), angiogenesis (p < 0.01) and cell proliferation (p < 0.001) compared to vehicle control, 1 µM AP39 further increased granulation tissue formation compared to other frostbite groups (p < 0.001). Thus, AP39 promoted frostbite wound healing, and therefore could be considered as a treatment option for patients with frostbite injury.

Intracellular protein aggregation causes proteotoxic stress, underlying highly debilitating neurodegenerative disorders in parallel with decreased proteasome activity. Nevertheless, under such stress conditions, the expression of proteasome subunits is upregulated by Nuclear Factor Erythroid 2-related factor 1 (NRF1), a transcription factor that is encoded by NFE2L1. Activating the NRF1 pathway could accordingly delay the onset of neurodegenerative and other disorders with impaired cell proteostasis. Here, we present a series of small-molecule compounds based on bis(phenylmethylen)cycloalkanones and their heterocyclic analogues, identified via targeted library screening, that can induce NRF1-dependent downstream events, such as proteasome synthesis, heat shock response, and autophagy, in both model cell lines and Caenorhabditis elegans strains. These compounds increase proteasome activity and decrease the size and number of protein aggregates without causing any cellular stress or inhibiting the ubiquitin-proteasome system (UPS). Therefore, our compounds represent a new promising therapeutic approach for various protein conformational diseases, including the most debilitating neurodegenerative diseases.