Chemico-Biological Interactions最新文献

The prevalence and mortality rates of colorectal cancer have been increasing in recent years, driven in part by the reliance of cancerous cells on aerobic glycolysis for growth. Sodium butyrate (NaB) has been shown to impede this process in colorectal cancer cells, although its mechanism of action remains unclear. In this study, we used cobalt chloride (CoCl₂) to simulate a hypoxic environment and demonstrated that NaB downregulated hypoxia-inducible factor-1α (HIF-1α) protein levels under both normoxic and hypoxic conditions. By employing cycloheximide (CHX), MG132, and chloroquine (CQ), we investigated whether NaB affects HIF-1α protein levels via the autophagy pathway. Importantly, siRNA-mediated SIRT4 knockdown revealed that NaB promotes HIF-1α autophagic degradation by upregulating SIRT4 expression. This subsequently inhibits HIF-1α-mediated expression of GLUT1 and LDHA, reducing glucose uptake, lactate production, and ATP generation, ultimately suppressing aerobic glycolysis and cell proliferation in colorectal cancer cells. Furthermore, a human colorectal cancer xenograft model confirmed that butyric acid inhibited tumor growth in vivo, correlating with SIRT4 and HIF-1α modulation. In conclusion, our findings indicate that NaB hinders colorectal cancer progression by disrupting aerobic glycolysis mediated by SIRT4/HIF-1α.

The unknown mechanism that controls intestinal barrier dysfunction in individuals with Crohn's disease (CD) plays a crucial role in the onset of intestinal inflammation. Testin, an intercellular linker protein, has the potential to protect epithelial barrier function. This study aimed to analyse the effects of Testin on CD-like colitis and explore the possible underlying mechanism. Colon samples from CD patients and trinitrobenzene-sulfonic acid (TNBS)-treated mice were collected to examine changes in Testin expression. To assess the therapeutic effects of Testin on CD-like colitis in mice, we examined the symptoms of enteritis, performed histological analysis, and evaluated intestinal barrier permeability. The ability of Testin to stabilize tight junction (TJ) proteins was investigated via immunofluorescence and western blotting. We conducted in vivo and in vitro experiments using colonic organoids and blocking techniques to explore how Testin safeguards the integrity of the intestinal barrier. Testin expression was downregulated in the colons of CD patients and TNBS-treated mice. Increasing Testin expression led to amelioration of colitis symptoms and reduced the production of inflammatory cytokines in the colons of TNBS-induced colitis model mice. Furthermore, increased Testin expression resulted in decreased depletion of TJ proteins (ZO-1 and Claudin-1) and promoted the effectiveness of the intestinal barrier in mice with TNBS-induced colon damage and in lipopolysaccharide (LPS)-stimulated colonic organoids. Elevated Testin levels inactivated the JNK/P38 signalling pathway, potentially contributing to the beneficial impact of Testin on the intestinal barrier. Testin can inhibit the loss of TJ proteins in CD mice by inactivating the JNK/P38 pathway. These findings help to clarify how Testin alleviates CD-like colitis in mice by protecting intestinal barrier function. These findings could lead to the use of a new treatment approach for CD in clinical practice.

Exosomes play a crucial role in regulating extracellular communication between normal and cancer cells within the tumor microenvironment, thereby affecting tumor progression through their cargo molecules. However, the specific impact of exosomal circular RNAs (circRNAs) on the development of cadmium-induced carcinogenesis remains unclear. To address this, we investigated whether exosomes derived from normal human bronchial epithelial BEAS-2B (N–B2B) cells could transmit circRNA to cadmium-transformed BEAS-2B (Cd–B2B) cells and the potential effects on Cd–B2B cells. Our findings demonstrated a significant downregulation of circ_0004664 in Cd–B2B cells compared to N–B2B cells (P < 0.01). Overexpression of circ_0004664 in Cd–B2B cells led to a significant inhibition of cell migration and invasion (P < 0.01 or P < 0.05). Furthermore, N–B2B cells could transfer circ_0004664 into recipient Cd–B2B cells via exosomes, subsequently inhibiting cell migration and invasion (P < 0.05 or P < 0.01). Mechanistic investigations revealed that exosomal circ_0004664 functioned as a competitive endogenous RNA for miR-942-5p, resulting in an upregulation of PTEN (P < 0.05). Our study highlights the involvement of exosomal circ_0004664 in cell-cell communication during cadmium carcinogenesis, providing a novel insight into the role of exosomal circRNA in this process.

Hydrogen sulfide (H₂S), an endogenous gasotransmitter, plays a key role in several critical physiological and pathological processes in vivo, including vasodilation, anti-infection, anti-tumor, anti-inflammation, and angiogenesis. In colorectal cancer (CRC), aberrant overexpression of H₂S-producing enzymes has been observed. Due to the important role of H₂S in the proliferation, growth, and death of cancer cells, H₂S can serve as a potential target for cancer therapy. In this review, we thoroughly analyzed the underlying mechanism of action of H₂S in CRC from the following aspects: the synthesis and catabolism of H₂S in CRC cells and its effect on cell signal transduction pathways; the inhibition effects of exogenous H₂S donors with different concentrations on the growth of CRC cells and the underlying mechanism of H₂S in garlic and other natural products. Furthermore, we elucidate the expression characteristics of H₂S in CRC and construct a comprehensive H₂S-related signaling pathway network, which has important basic and practical significance for promoting the clinical research of H₂S-related drugs.

Following inhalation exposure to organophosphorus nerve agents, symptoms rapidly develop and severe respiratory symptoms, such as bronchorrhea and bronchoconstriction are the leading causes of lethality. Nerve agent-induced lung injury is little investigated and the standard treatment for symptomatic relief targets the enzyme acetylcholinesterase and muscarinic acetylcholine and GABAergic receptors. In the present study, cellular responses in lung tissue during the acute (40 min) and extended phase (24 h) following severe exposure to the nerve agent VX have been investigated using an ex vivo rat precision-cut lung slice model including electrostimulation to induce a cholinergic response. Changes in protein amount, cell viability, together with, inflammatory and oxidative stress markers have been determined in both the lung tissue and incubation medium.

During the acute phase, VX caused significantly increased airway contraction and decreased airway relaxation. Five micromolar of VX did not affect the sample protein levels and cell viability in lung tissue. Among seven markers of cellular responses investigated in the lung tissue, increased levels of heme oxygenase-1 and matrix metalloproteinase-9 together with decreased levels of glutathione in the incubation medium were observed in the acute phase following VX-exposure compared to electrostimulation only. No difference in cellular response was observed following VX-exposure for 24 h compared to the air control. In comparison, LPS-exposure resulted in time-dependent changes in all markers of inflammation and oxidative response.

In conclusion, the present study demonstrated VX-specific patterns of oxidative responses in the lung, as well as, signs of inflammatory response and remodelling of extracellular matrix. These potential mechanisms of tissue injury should be further investigated for their potential as additional therapeutic targets during the acute phase of intoxication.

Carbon monoxide (CO) poisoning presents a substantial public health challenge that necessitates the identification of its pathological mechanisms and therapeutic targets. CO toxicity arises from tissue hypoxia-ischemia secondary to carboxyhemoglobin formation, and cellular damage mediated by CO at the cellular level. The mitochondria are the major targets of neuronal damage caused by CO. Under normal physiological conditions, mitochondria produce reactive oxygen species (ROS), which are byproducts of aerobic metabolism. While low ROS levels are crucial for essential cellular functions, including signal transduction, differentiation, responses to hypoxia and immunity, transcriptional regulation, and autophagy, excess ROS become pathological and exacerbate CO poisoning. This review presents the evidence of elevated ROS being associated with the progression of CO poisoning. Antioxidant treatments targeting ROS removal have been proven effective in mitigating CO poisoning, underscoring their therapeutic potential. In this review, we highlight the latest advances in the understanding of the role and the clinical implications of ROS in CO poisoning. We focus on cellular sources of ROS, the molecular mechanisms underlying mitochondrial oxidative stress, and potential therapeutic strategies for targeting ROS in CO poisoning.

Parkinson's disease (PD) poses a formidable challenge in neurology, marked by progressive neuronal loss in the substantia nigra. Despite extensive investigations, understanding PD's pathophysiology remains elusive, with no effective therapeutic intervention identified to alter its course. Oxyphylla A (OPA), a natural compound extracted from Alpinia oxyphylla, exhibits promise in experimental models of various neurodegenerative disorders (ND), notably through novel mechanisms like α-synuclein degradation. The purpose of this investigation was to explore the neuroprotective potential of OPA on 6-hydroxydopamine (6-OHDA)-induced neurotoxicity in PD models, with a focus on mitochondrial functions. Additionally, potential OPA targets for neuroprotection were explored. PC12 cells and C57BL/6 mice were lesioned with 6-OHDA as PD models. Impaired mitochondrial membrane potential (Δψm) was assessed using JC-1 staining. The oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) were also detected to evaluate mitochondrial function and glucose metabolism in PC12 cells. Behavioral analysis and immunohistochemistry were performed to evaluate pathological lesions in the mouse brain. Moreover, bioinformatics tools predicted OPA targets. OPA restored cellular energy metabolism and mitochondrial biogenesis, preserving Δψm in 6-OHDA-induced neuronal damage. Pre-treatment mitigated loss of tyrosine hydroxylase (TH)-positive neurons in the substantia nigra and striatal dopaminergic fibers, restoring dopamine levels and ameliorating motor deficits in PD mice. Mechanistically, OPA may activate PKA/Akt/GSK-3β and CREB/PGC-1α/NRF-1/TFAM signaling cascades. Bioinformatics analysis identified potential OPA targets, including CTNNB1, ESR1, MAPK1, MAPK14, and SRC. OPA, derived from Alpinia oxyphylla, exhibited promising neuroprotective activity against PD through addressing mitochondrial dysfunction, suggesting its potential as a multi-targeted therapeutic for PD.

Current medical countermeasures (MCMs) for nerve agent poisoning have limited efficacy, and can cause serious adverse effects, prompting the requirement for new broad-spectrum therapeutics. Human plasma-derived butyrylcholinseterase (huBChE) is a promising novel bioscavenger MCM which has shown potential in animal studies, however, is economically prohibitive to manufacture at scale. This study addresses current challenges for the economical production of a bioactive and long-acting recombinant huBChE (rBChE) in mammalian cells by being the first to directly compare novel rBChE design strategies. These include co-expression of a proline rich attachment domain (PRAD) and fusion of BChE with a protein partner. Additionally, a pre-purification screening method developed in this study enables parallel comparison of the expression efficiency, activity and broad-spectrum binding to nerve agents for ten novel rBChE molecular designs. All designed rBChE demonstrated functionality to act as broad-spectrum MCMs to G, V and A series nerve agents. Expression using the ExpiCHO™ Max protocol provided greatest expression levels and activity for all constructs, with most rBChE expressing poorly in Expi293™. Fc- or hSA-fused rBChE significantly outperformed constructs designed to mimic huBChE, including PRAD-BChE, and proved an effective strategy to significantly improve enzyme activity and expression. Choice of protein partner, directionality and the addition of a linker also impacted fusion rBChE activity and expression. Overall, hSA fused rBChE provided greatest expression yield and activity, with BChE-hSA the best performing construct. The purified and characterised BChE-hSA demonstrated similar functionality to huBChE to be inhibited by GD, VX and A-234, supporting the findings of the pre-screening study and validating its capacity to assess and streamline the selection process for rBChE constructs in a cost-effective manner. Collectively, these outcomes contribute to risk mitigation in early-stage development, providing a systematic method to compare rBChE designs and a focus for future development.

Leishmaniasis is a neglected tropical disease caused by parasites of the genus Leishmania and is responsible for more than 1 million new cases and 70,000 deaths annually worldwide. Treatment has high costs, toxicity, complex and long administration time, several adverse effects, and drug-resistant strains, therefore new therapies are urgently needed. Synthetic compounds have been highlighted in the medicinal chemistry field as a strong option for drug development against different diseases. Organic salts (OS) have multiple biological activities, including activity against protozoa such as Leishmania spp. This study aimed to investigate the in vitro leishmanicidal activity and death mechanisms of a thiohydantoin salt derived from l-arginine (ThS) against Leishmania amazonensis. We observed that ThS treatment inhibited promastigote proliferation, increased ROS production, phosphatidylserine exposure and plasma membrane permeabilization, loss of mitochondrial membrane potential, lipid body accumulation, autophagic vacuole formation, cell cycle alteration, and morphological and ultrastructural changes, showing parasites death. Additionally, ThS presents low cytotoxicity in murine macrophages (J774A.1), human monocytes (THP-1), and sheep erythrocytes. ThS in vitro cell treatment reduced the percentage of infected macrophages and the number of amastigotes per macrophage by increasing ROS production and reducing TNF-α levels. These results highlight the potential of ThS among thiohydantoins, mainly related to the arginine portion, as a leishmanicidal drug for future drug strategies for leishmaniasis treatment. Notably, in silico investigation of key targets from L. amazonensis, revealed that a ThS compound from the l-arginine amino acid strongly interacts with arginase (ARG) and TNF-α converting enzyme (TACE), suggesting its potential as a Leishmania inhibitor.

Long-term hyperuricemia can induce kidney damage, clinically referred to as hyperuricemic nephropathy (HN), which is characterized by renal fibrosis, inflammation, and oxidative stress. However, currently used uric acid-lowering drugs are not capable of protecting the kidneys from damage. Therefore, uric acid-lowering drugs that can also protect the kidneys are urgently needed. In this study, we first discovered that salinomycin, an antibiotic, can regulate uric acid homeostasis and ameliorate kidney damage in mice with HN. Mechanistically, salinomycin inhibited serum and hepatic xanthine oxidase (XOD) activities and downregulated renal urate transporter 1 (URAT1) expression and transport activity, thus exerting uric acid-lowering effects in mice with HN. Furthermore, we found that salinomycin promoted p-NRF2 Ser40 expression, resulting in increased nuclear translocation of NRF2 and activation of NRF2. More importantly, salinomycin affected the gut microbiota and promoted the generation of short-chain fatty acids (SCFAs) in mice with HN. In conclusion, our results revealed that salinomycin maintains uric acid homeostasis and alleviates kidney injury in mice with HN by multiple mechanisms, suggesting that salinomycin might be a desirable candidate for HN treatment in the clinic.