Quercetin inclusion complex gels ameliorate radiation-induced brain injury by regulating gut microbiota

Oral quercetin nanoparticles in hydrogel microspheres alleviate high-altitude sleep disturbance based on the gut-brain axis

High-altitude sleep disturbance is a common symptom of acute mountain sickness, which can be alleviated via modulation of the gut-brain axis. Quercetin (Que) is used to modulate gut microbiota and serves as a potential drug to regulate the gut-brain axis, but the poor solubility and bioavailability affect its biological functions. Here, Que nanoparticles (QNPs) were prepared with zein using an antisolvent method, and QNP-loaded calcium alginate hydrogel microspheres (QNP@HMs) were prepared using electrospinning technology to improve the gastrointestinal stability and intestinal adhesion of QNPs. In the mouse model of high-altitude sleep disturbance, oral administration of QNP@HMs before the mice entering high altitude prolonged sleep duration, improved blood cell recovery, spontaneous behavior and short-term memory, and reduced such inflammation factors as TNF-α and iNOS. Moreover, QNP@HMs enhanced the abundance of probiotics in the gut, including Lactobacillus and Lachnospira, and reduced intestinal inflammation. However, in the mice after gut sterilization by long-term oral antibiotics, QNP@HMs showed no therapeutic effect. QNP@HMs are a promising medication for the prevention of high-altitude sleep disturbance based on the gut-brain axis.

Dietary (Poly)phenols and the Gut-Brain Axis in Ageing

As the population ages, the incidence of age-related neurodegenerative diseases is rapidly increasing, and novel approaches to mitigate this soaring prevalence are sorely needed. Recent studies have highlighted the importance of gut microbial homeostasis and its impact on brain functions, commonly referred to as the gut-brain axis, in maintaining overall health and wellbeing. Nonetheless, the mechanisms by which this system acts remains poorly defined. In this review, we will explore how (poly)phenols, a class of natural compounds found in many plant-based foods and beverages, can modulate the gut-brain axis, and thereby promote neural health. While evidence indicates a beneficial role of (poly)phenol consumption as part of a balanced diet, human studies are scarce and mechanistic insight is still lacking. In this regard, we make the case that dietary (poly)phenols should be further explored to establish their therapeutic efficacy on brain health through modulation of the gut-brain axis, with much greater emphasis on carefully designed human interventions.

Oral Curcumin-Thioketal-Inulin Conjugate Micelles against Radiation-Induced Enteritis

Radiation-induced enteritis is an unavoidable complication associated with pelvic tumor radiotherapy, significantly influencing the prognosis of cancer patients. The limited availability of commercial gastrointestinal radioprotectors in clinical settings poses a substantial challenge in preventing radiation enteritis. Despite the inherent radioprotective characteristics of Cur in vitro, its poor solubility in water, instability, and low bioavailability lead to inferior therapeutic effects in vivo. Herein, we developed novel ROS-responsive micelles (CTI) from inulin and curcumin, aimed at mitigating radiation enteritis. CTI micelles had excellent solubility and stability. Importantly, CTI improved the cytotoxicity and bioavailability of curcumin, thereby showing enhanced effectiveness in neutralizing ROS induced by radiation, safeguarding against DNA damage, and reducing radiation-induced cellular mortality. Moreover, in a radiation enteritis mice model, CTI not only alleviated severe radiation-induced intestinal injury but also improved redox-related indicators and reduced inflammatory cytokine expression. Furthermore, CTI effectively increased gut microbiota abundance and maintained gut homeostasis. In conclusion, CTI could be a promising candidate for the clinical management of radiation enteritis. Our study provides a new perspective for radioprotection using natural antioxidants.

Radiation enteropathy-related depression: A neglectable course of disease by gut bacterial dysbiosis

Radiation enteropathy (RE) is common in patients treated with radiotherapy for pelvic-abdominal cancers. Accumulating data indicate that gut commensal bacteria determine intestinal radiosensitivity. Radiotherapy can result in gut bacterial dysbiosis. Gut bacterial dysbiosis contributes to the pathogenesis of RE. Mild to moderate depressive symptoms can be observed in patients with RE in clinical settings; however, the rate of these symptoms has not been reported. Studies have demonstrated that gut bacterial dysbiosis induces depression. In the state of comorbidity, RE and depression may be understood as local and abscopal manifestations of gut bacterial disorders. The ability of comorbid depression to worsen inflammatory bowel disease (IBD) has long been demonstrated and is associated with dysfunction of cholinergic neural anti-inflammatory pathways. There is a lack of direct evidence for RE comorbid with depression. It is widely accepted that RE shares similar pathophysiologic mechanisms with IBD. Therefore, we may be able to draw on the findings of the relationship between IBD and depression. This review will explore the relationship between gut bacteria, RE, and depression in light of the available evidence and indicate a method for investigating the mechanisms of RE combined with depression. We will also describe new developments in the treatment of RE with probiotics, prebiotics, and fecal microbial transplantation.

Chlorine-doped MoS2 quantum dots embedded in a molecularly imprinted polymer for highly selective and sensitive optosensing of quercetin

Chlorine-doped MoS2 quantum dots (Cl-MoS2 QDs) embedded in a SiO2 molecularly imprinted polymer (Cl-MoS2 QDs@SiO2@MIP) have been successfully synthesized and can be used for highly selective and sensitive optosensing of quercetin. The novel environmentally friendly sensor integrated the advantages of the Cl-MoS2 QDs and MIP, high sensitivity and specific recognition for quercetin. The as-fabricated sensor is used to detect trace amounts of quercetin, and its fluorescence intensity showed a good linear decline with the increasing concentration of quercetin from 2 ng mL-1 to 200 ng mL-1 with a detection limit of 1.2 ng mL-1 (S/N = 3). The Cl-MoS2 QDs@SiO2@MIP probe was employed to assay the content of quercetin of real onion extract with good performance, which is in fine agreement with the result obtained by high performance liquid chromatography. The developed Cl-MoS2 QDs@SiO2@MIP sensor exhibits promising potential in the detection of quercetin.

The effects of Lactobacillus reuteri microcapsules on radiation-induced brain injury by regulating the gut microenvironment

A radiation-induced brain injury (RIBI) is a major adverse event following radiotherapy of malignant tumors. RIBI would affect cognitive function, leading to a series of complications and even death. However, the pathogenesis of RIBI is still unclear, and it still lacks specific therapeutic drugs. The gut-brain bidirectional communication may be mediated by various microbiota and metabolites in the gastrointestinal tract. Probiotics are closely related to physiological health. The theory of the gut-brain axis provides us with a new idea to improve the gut microenvironment by supplementing probiotics against RIBI. Here, Lactobacillus reuteri microcapsules (LMCs) were prepared, which were predominantly irregular spheres with a rough surface under a scanning electron microscope and a narrow size distribution ranging from 20 to 700 μm. The transmission electron microscopy images showed that the structure of microcapsules containing Lactobacillus reuteri (L. reuteri) was a core and shell structure. The survival of L. reuteri in microcapsules was significantly more than that of free L. reuteri in the simulated stomach environment of pH 1.2. 16S rDNA sequencing showed that LMCs observably increased the relative abundance of Lactobacillus in RIBI mice. More importantly, compared with the RIBI model mice, the behavior of RIBI mice treated with LMCs was significantly improved. In addition, LMCs greatly alleviated the pathological damage of the hippocampus and intestines in the mice after irradiation and reduced the level of TNF-α and IL-6 in vivo. Generally, LMCs are a promising oral preparation, which provide new ideas and methods for the treatment of RIBI.

Emerging trends and focus of research on the relationship between traumatic brain injury and gut microbiota: a visualized study

Background

Traumatic brain injury (TBI) is one of the most serious types of trauma and imposes a heavy social and economic burden on healthcare systems worldwide. The development of emerging biotechnologies is uncovering the relationship between TBI and gut flora, and gut flora as a potential intervention target is of increasing interest to researchers. Nevertheless, there is a paucity of research employing bibliometric methodologies to scrutinize the interrelation between these two. Therefore, this study visualized the relationship between TBI and gut flora based on bibliometric methods to reveal research trends and hotspots in the field. The ultimate objective is to catalyze progress in the preclinical and clinical evolution of strategies for treating and managing TBI.

Methods

Terms related to TBI and gut microbiota were combined to search the Scopus database for relevant documents from inception to February 2023. Visual analysis was performed using CiteSpace and VOSviewer.

Results

From September 1972 to February 2023, 2,957 documents published from 98 countries or regions were analyzed. The number of published studies on the relationship between TBI and gut flora has risen exponentially, with the United States, China, and the United Kingdom being representative of countries publishing in related fields. Research has formed strong collaborations around highly productive authors, but there is a relative lack of international cooperation. Research in this area is mainly published in high-impact journals in the field of neurology. The "intestinal microbiota and its metabolites," "interventions," "mechanism of action" and "other diseases associated with traumatic brain injury" are the most promising and valuable research sites. Targeting the gut flora to elucidate the mechanisms for the development of the course of TBI and to develop precisely targeted interventions and clinical management of TBI comorbidities are of great significant research direction and of interest to researchers.

Conclusion

The findings suggest that close attention should be paid to the relationship between gut microbiota and TBI, especially the interaction, potential mechanisms, development of emerging interventions, and treatment of TBI comorbidities. Further investigation is needed to understand the causal relationship between gut flora and TBI and its specific mechanisms, especially the "brain-gut microbial axis."

Drug design strategies that aim to improve the low solubility and poor bioavailability conundrum in quercetin derivatives

INTRODUCTION

Scientists are especially interested in polyphenols, particularly flavonoids. Quercetin, a flavonoid, has demonstrated various therapeutic properties, such as antioxidant, anti-diabetic, anti-hypertensive, and anti-carcinogenic activities. Different plant sources contain varying quantities and types of quercetin. However, quercetin's bioavailability is frequently low due to its low water solubility, molecular stability, and absorption characteristics.

AREAS COVERED

The primary goals of this review are related to the approaches for overcoming quercetin's limitations. Hence, the main tactics for structural modifications (addition of charged and polar groups, removing C2, C3 double bond or reducing aromaticity, disrupting intramolecular H-bond, and reducing crystal lattice stability) and drug delivery systems (cyclodextrin complexes, emulsions, nanoparticles, liposomes, etc.) were discussed to improve water solubility and bioavailability of quercetin.

EXPERT OPINION

From a tactical perspective, enhancing the solubility of compounds can be simplified through decreasing hydrophobic properties or crystalline stability. In addition, an essential field of study focuses on creating appropriate molecular carriers for substances with low water solubility. However, pharmacokinetics, potency, and toxicology are all impacted by the structural factors and physical characteristics that regulate solubility. Poor water solubility is still a major problem in drug discovery, and new methods are always in demand to overcome it.

Effect of stem cell conditional medium-loading adhesive hydrogel on TGF-β1-induced endometrial stromal cell fibrosis

Introduction: Uterine adhesion (IUA) is a severe complication that results from uterine operations or uterine infections. Hysteroscopy is considered the gold standard for the diagnosis and treatment of uterine adhesions. Yet, this invasive procedure leads to re-adhesions after hysteroscopic treatment. Hydrogels loading functional additives (e.g., placental mesenchymal stem cells (PC-MSCs)) that can act as physical barriers and promote endometrium regeneration are a good solution. However, traditional hydrogels lack tissue adhesion which makes them unstable under a rapid turnover of the uterus, and PC-MSCs have biosafety risks when used as functional additives. Methods: In this study, we coupled an adhesive hydrogel with a PC-MSCs conditioned medium (CM) to form a hybrid of gel and functional additives (CM/Gel-MA). Results and Discussion: Our experiments show that CM/Gel-MA enhances the activity of endometrial stromal cells (ESCs), promotes cell proliferation, and reduces the expression of α-SMA, collagen I, CTGF, E-cadherin, and IL-6, which helps to reduce the inflammatory response and inhibit fibrosis. We conclude that CM/Gel-MA can more potentially prevent IUA by combining the physical barriers from adhesive hydrogel and functional promotion from CM.

Gut microbiota and ionizing radiation-induced damage: Is there a link?

According to observational findings, ionizing radiation (IR) triggers dysbiosis of the intestinal microbiota, affecting the structural composition, function, and species of the gut microbiome and its metabolites. These modifications can further exacerbate IR-induced damage and amplify proinflammatory immune responses. Conversely, commensal bacteria and favorable metabolites can remodel the IR-disturbed gut microbial structure, promote a balance between anti-inflammatory and proinflammatory mechanisms in the body, and mitigate IR toxicity. The discovery of effective and safe remedies to prevent and treat radiation-induced injuries is vitally needed because of the proliferation of radiation toxicity threats produced by recent radiological public health disasters and increasing medical exposures. This review examines how the gut microbiota and its metabolites are linked to the processes of IR-induced harm. We highlight protective measures based on interventions with gut microbes to optimize the distress caused by IR damage to human health. We offer prospects for research in emerging and promising areas targeting the prevention and treatment of IR-induced damage.