Anti-inflammatory and antioxidant effects of the nanocomposite Fullerol decrease the severity of intestinal inflammation induced by gut ischemia and reperfusion

Electroacupuncture Improves Intestinal Ischemia/Reperfusion Injury via cGAS-STING Pathway

BACKGROUND

Electroacupuncture (EA) is a treatment method that stimulates acupuncture points to mobilize resistance to disease and bioelectricity to achieve therapeutic effects. Related studies have found that EA has a certain therapeutic effect on ischemia/reperfusion (I/R) injury of some organs. Among the internal organs, the intestine is the most sensitive to ischemic injury. Therefore, this study aims to preliminarily explore the effects and mechanisms of EA on intestinal I/R injury through animal experiments and provide a theoretical basis for the clinical treatment of intestinal I/R injury.

METHODS

In this study, the intestinal I/R injury model was established by occluding the superior mesenteric artery (SMA) of mice for 45 min and then reperfusing for 2 h. By applying EA to the bilateral Zusanli in mice, this study aimed to investigate its therapeutic effects on intestinal I/R injury.

KEY RESULTS

The results showed that EA can improve the survival and nutritional status of mice with intestinal I/R injury. EA alleviated intestinal tissue damage and the inflammatory response induced by intestinal I/R injury and protected the integrity of intestinal epithelial cells and intestinal transport function. Inflammatory factors induced by intestinal I/R injury were associated with increased levels of STING, and EA could inhibit the increase in STING protein levels and the phosphorylation of downstream factors IRF3 and TBK1 of the cGAS-STING pathway.

CONCLUSIONS

EA can alleviate intestinal tissue damage caused by intestinal I/R in mice, protect the intestinal epithelial barrier, and improve intestinal transit function. The underlying mechanism may involve inhibition of cGAS-STING pathway activation and reduction of the inflammatory response.

Apigenin Alleviates Intestinal Ischemia/Reperfusion Injury via Upregulating Nrf2-Mediated Tight Junction Integrity

Epithelial barrier dysfunction, critically involved in intestinal ischemia/reperfusion (I/R) injury, is significantly regulated by Nrf2-mediated oxidative stress. Apigenin, a flavonoid commonly found in fruits and vegetables with diverse biological properties, has an unclear impact on intestinal I/R injury. We hypothesize that apigenin improves intestinal barrier dysfunction by activating Nrf2 signaling. Thirty rats were randomly divided into five groups to establish an I/R model using superior mesenteric artery occlusion. Hypoxia and re-oxygenation (H/R) model was developed utilizing Caco-2 and IEC-6 cells, which were exposed to hypoxic conditions followed by re-oxygenation. Apigenin protected against intestinal mucosal damage by suppressing inflammatory cytokines release (TNF-α, IL-1β, IL-6, MPO, p < 0.01), ameliorating oxidative stress (MDA, SOD, GSH, GSH-Px, p < 0.01), and improving barrier dysfunction (DAO and TEER, p < 0.01) both in vivo and in vitro, without causing significant changes in the corresponding normal controls (p > 0.05). Apigenin up-regulated the protein expression of Nrf2, HO-1, and tight junction (TJ) proteins (p < 0.01). Furthermore, the knockdown of Nrf2 significantly abrogated apigenin-enhanced the TJ expression. Apigenin pretreatment alleviates intestinal I/R-induced barrier damage through Nrf2 activation and TJ upregulation, offering new strategies for preventing or treating I/R-associated intestinal diseases.

pH-responsive cationic polymer-functionalized poly-ε-caprolactone microspheres scavenge cell-free-DNA to alleviate intestinal ischemia/reperfusion injury by inhibiting M1 macrophage polarization

Intestinal ischemia/reperfusion (I/R) injury is a common life-threatening condition. Inflammatory dysregulation plays a crucial role in the pathological progression of intestinal I/R injury, indicating that controlling excessive inflammatory responses can be an effective strategy for mitigating I/R injury. Herein, after establishing a correlation between cell-free DNA (cfDNA) levels and postoperative inflammatory factors in samples from patients with intestinal I/R, we tested a cfDNA-scavenging approach for the treatment of intestinal I/R injury. Poly-ε-caprolactone (PCL) microspheres (Micro DEA2k) functionalized with a pH-responsive cationic polymer (DEA2k) to efficiently scavenge cfDNA were synthesized and evaluated.These microspheres exhibited enhanced cfDNA adsorption under inflammation-induced acidic conditions, along with low toxicity, reduced non-specific protein binding, and extended peritoneal retention. In a mouse model of intestinal I/R injury, the intraperitoneal injection Micro DEA2k effectively bound cfDNA, regulated the mononuclear phagocytic system, decreased the number of M1 macrophages, suppressed inflammation, and significantly improved the survival rate of the mice. These findings suggest that cfDNA scavenging using cationic microspheres has considerable potential for alleviating intestinal I/R injury.

Fullerenes in vivo. Toxicity and protective effects

The data available in the literature on the toxicity of fullerenes are numerous but contradictory. The ambiguity of research results hinders the transition from scientific research to real-world drug development. The ability of fullerenes to accumulate in some organs and tissues is interpreted in most cases as their disadvantage, while a number of studies have shown that there is no relationship between the accumulation of fullerenes and toxic effects. Moreover, fullerenes often exert potent protective effects. The pharmacokinetics and toxicity of fullerenes depend on the route of administration and are closely related to their functionalization, since pristine fullerenes are generally harmless. These factors, as well as the risk-benefit ratio, need to be considered when developing fullerene-based drugs. In this review, open-source data on in vivo toxicity, biodistribution, metabolism, and some protective properties of both native fullerene and a number of its derivatives are collected and analyzed. The problems and prospects for using fullerenes through various methods of delivery to the body, such as through the gastrointestinal tract, intravenous administration, intraperitoneal administration, dermal application or respiratory exposure are described.

Suppressing the Aging Phenotype of Mesenchymal Stromal Cells: Are We Ready for Clinical Translation?

Mesenchymal stem/stromal cells (MSCs) are involved in the maintenance and regeneration of a large variety of tissues due to their stemness and multi-lineage differentiation capability. Harnessing these advantageous features, a flurry of clinical trials have focused on MSCs to treat different pathologies, but only few protocols have received regulatory approval so far. Among the various causes hindering MSCs' efficacy is the emergence of cellular senescence, which has been correlated with specific characteristics, such as morphological and epigenetic alterations, DNA damage, ROS production, mitochondrial dysfunction, telomere shortening, non-coding RNAs, loss of proteostasis, and a peculiar senescence-associated secretory phenotype. Several strategies have been investigated for delaying or even hopefully reverting the onset of senescence, as assessed by the senescent phenotype of MSCs. Here, the authors reviewed the most updated literature on the potential causes of senescence, with a particular emphasis on the current and future therapeutic approaches aimed at reverting senescence and/or extending the functional lifespan of stem cells.

Recent Progress of Oral Functional Nanomaterials for Intestinal Microbiota Regulation

The gut microbiota is closely associated with human health, and alterations in gut microbiota can influence various physiological and pathological activities in the human body. Therefore, microbiota regulation has become an important strategy in current disease treatment, albeit facing numerous challenges. Nanomaterials, owing to their excellent protective properties, drug release capabilities, targeting abilities, and good biocompatibility, have been widely developed and utilized in pharmaceuticals and dietary fields. In recent years, significant progress has been made in research on utilizing nanomaterials to assist in regulating gut microbiota for disease intervention. This review explores the latest advancements in the application of nanomaterials for microbiota regulation and offers insights into the future development of nanomaterials in modulating gut microbiota.

Targeting cell death pathways in intestinal ischemia-reperfusion injury: a comprehensive review

Intestinal ischemia-reperfusion (I/R) is a multifaceted pathological process, and there is a lack of clear treatment for intestinal I/R injury. During intestinal I/R, oxidative stress and inflammation triggered by cells can trigger a variety of cell death mechanisms, including apoptosis, autophagy, pyroptosis, ferroptosis, and necrosis. These cell death processes can send a danger signal for the body to be damaged and prevent intestinal I/R injury. Therefore, identifying key regulatory molecules or markers of these cell death mechanisms when intestinal I/R injury occurs may provide valuable information for the treatment of intestinal I/R injury. This paper reviews the regulatory molecules and potential markers that may be involved in regulating cell death during intestinal I/R and elaborates on the cell death mechanism of intestinal I/R injury at the molecular level to provide a theoretical basis for discovering new molecules or markers regulating cell death during intestinal I/R injury and provides ideas for drug development for the treatment of intestinal I/R injury.

Network pharmacology analysis combined with experimental validation to explore the therapeutic mechanism of salidroside on intestine ischemia reperfusion

ETHNOPHARMACOLOGICAL RELEVANCE

Salidroside (SAL), a phenolic natural product present in Rhodiola rosea, are commonly used in the treatment of various ischemic-hypoxic diseases, including intestinal ischemia-reperfusion (IR) injury. However, their efficacy and potential mechanisms in the treatment of intestinal IR injury have not been investigated.

OBJECTIVE

The objective of the present study is to investigate the pharmacological mechanism of action of SAL on intestinal IR injury using a network pharmacology approach combined with experimental validation.

METHODS

In the present study, we used the Traditional Chinese Medicine Systematic Pharmacology (TCMSP) database and analysis platform and Comparative Toxicogenomics Database (CTD) to predict possible target genes of SAL, collected relevant target genes of intestinal IR injury from GeneCards and DisGenet websites, and collected summary data to screen common target genes. Then, the protein-protein interaction (PPI) target network was constructed and analyzed by STRING database and Cytoscape 3.8.2 with the above intersecting genes. Then, gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed and the component-target-pathway network was constructed, followed by the use of molecular docking and molecular dynamic simulation to verify the possible binding conformation between SAL and candidate targets to further explore the potential targets of SAL in the treatment of intestinal IR injury. Finally, an in vivo model of mouse superior mesenteric artery ligation was established to assess the anti-intestinal IR injury effect of SAL by assessing histopathological changes in mouse small intestine by HE staining, detecting inflammatory factor expression by ELISA kit, and detecting the expression of key protein targets by Western blotting.

RESULTS

A total of 166 SAL target genes and 1740 disease-related targets were retrieved, and 88 overlapping proteins were obtained as potential therapeutic targets. The pathway enrichment analysis revealed that the pharmacological effects of SAL on intestinal IR injury were anti-hypoxic, anti-inflammatory and metabolic pathway related, and the molecular docking and molecular dynamic simulation results showed that the core bioactive components had good binding affinity for TXNIP and AMPK, and the immunoblotting results indicated that the expression levels of TXNIP and AMPK in the small intestinal tissues of mice in the drug-treated group compared with the model group were significantly changed.

CONCLUSION

SAL may target AMPK and TXNIP domains to act as a therapeutic agent for intestinal IR. These findings comprehensively reveal the potential therapeutic targets for SAL against intestinal IR and provide theoretical basis for the clinical application of SAL in the treatment of intestinal IR.

Novel antidepressant-like properties of the fullerenol in an LPS-induced depressive mouse model

Depression is a common mental disease and is highly prevalent in populations. Dysregulated neuroinflammation and concomitant-activated microglia are involved in the pathogenesis of depression. Experimental evidence has indicated that fullerenol exerts anti-neuroinflammation and protective effects against neurological diseases. Here, we evaluated fullerenol's effects against lipopolysaccharide (LPS)-induced mouse depressive-like behaviors. Fullerenol treatment produced an antidepressant-like effect, as indicated by preventing the LPS-induced reduction in the sucrose preference and shortening the immobility durations in both the tail suspension test and the forced swim test. We found that fullerenol treatment mitigated LPS-induced hippocampal microglia activation and released proinflammatory cytokines. Meanwhile, fullerenol promoted hippocampus neurogenesis, evidenced by increased DCX-positive cells in LPS-treated mice. Hippocampal RNA-Seq analysis revealed proinflammatory cytokine and neurogenesis involved in fullerenol's antidepressant-like effects. Our data indicate that fullerenol exerts antidepressant effects, which might be due to beneficial functions in reducing neuroinflammatory processes and promoting neurogenesis in the hippocampus.

Anti-Inflammatory Protein Isolated from Tamarind Promotes Better Histological Aspects in the Intestine Regardless of the Improvement of Intestinal Permeability in a Preclinical Study of Diet-Induced Obesity

Obesity is associated with metabolic and physiological effects in the gut. In this study, we evaluated the anti-inflammatory effect of trypsin inhibitor isolated from tamarind seeds (TTI) in vitro (interaction with lipopolysaccharide (LPS) and inhibitory activity against human neutrophil elastase (HNE)), and using intestinal co-cultures of Caco-2:HT29-MTX cell lines inflamed with TNF-α (50 ng/mL) and a Wistar rat model of diet-induced obesity (n = 15). TTI was administered to animals by gavage (10 days), and the treated group (25 mg/kg/day) was compared to animals without treatment or treated with a nutritionally adequate diet. In the in vitro study, it showed inhibitory activity against HNE (93%). In co-cultures, there was no protection or recovery of the integrity of inflamed cell monolayers treated with TTI (1.0 mg/mL). In animals, TTI led to lower plasma concentrations of TNF-α and IL-6, total leukocytes, fasting glucose, and LDL-c (p < 0.05). The intestines demonstrated a lower degree of chronic enteritis, greater preservation of the submucosa, and greater intestinal wall thickness than the other groups (p = 0.042). Therefore, the better appearance of the intestine not reflected in the intestinal permeability added to the in vitro activity against HNE point to possibilities for new studies and applications related to this activity.

Surface Activity and Aggregation Behavior of Polyhydroxylated Fullerenes in Aqueous Solutions

Polyhydroxylated fullerene (PHF) surface activity and aggregation behavior at the air-water interface were examined using surface tension and resonance-enhanced second harmonic generation (SHG). Surface tension data showed that PHFs are surface active with a limiting surface excess corresponding to 130 Ų/molecule in aqueous (Millipore water) solutions. Increasing the solution-phase ionic strength (through the addition of NaCl) reduces the PHF surface excess. Conductivity measurements show that PHFs carry a single charge, presumably negative. Surface-specific SHG experiments show a small but measurable fixed wavelength, nonlinear response from solutions having surface excess coverages as low as ∼400 Ų/molecule. The SHG response of PHF solutions in the low-concentration limit shows unexpected behavior, implying that at bulk concentrations below 0.06 mg/mL, PHF monomers adsorb to the surface and interfere destructively with the intrinsic nonlinear susceptibility of the aqueous/vapor interface, leading to a ∼75% reduction in the SH signal. Above a PHF concentration of 0.0.06 mg/mL, the SH signal begins to rise in the Millipore and 50 mM NaCl solutions but remains very low in the 500 mM NaCl solutions. From this behavior, we infer that an increased nonlinear optical response is due to adsorbed aggregates.

FcᵧRIIb protects from reperfusion injury by controlling antibody and type I IFN-mediated tissue injury and death

Intestinal ischemia and reperfusion (I/R) is accompanied by an exacerbated inflammatory response characterized by deposition of IgG, release of inflammatory mediators, and intense neutrophil influx in the small intestine, resulting in severe tissue injury and death. We hypothesized that FcᵧRIIb activation by deposited IgG could inhibit tissue damage during I/R. Our results showed that I/R induction led to the deposition of IgG in intestinal tissue during the reperfusion phase. Death upon I/R occurred earlier and was more frequent in FcᵧRIIb^-/- than WT mice. The higher lethality rate was associated with greater tissue injury and bacterial translocation to other organs. FcᵧRIIb^-/- mice presented changes in the amount and repertoire of circulating IgG, leading to increased IgG deposition in intestinal tissue upon reperfusion in these mice. Depletion of intestinal microbiota prevented antibody deposition and tissue damage in FcᵧRIIb^-/- mice submitted to I/R. We also observed increased production of ROS on neutrophils harvested from the intestines of FcᵧRIIb^-/- mice submitted to I/R. In contrast, FcᵧRIII^-/- mice presented reduced tissue damage and neutrophil influx after reperfusion injury, a phenotype reversed by FcᵧRIIb blockade. In addition, we observed reduced IFN-β expression in the intestines of FcᵧRIII^-/- mice after I/R, a phenotype that was also reverted by blocking FcᵧRIIb. IFNAR^-/- mice submitted to I/R presented reduced lethality and TNF release. Altogether our results demonstrate that antibody deposition triggers FcᵧRIIb to control IFN-β and IFNAR activation and subsequent TNF release, tailoring tissue damage, and death induced by reperfusion injury.