Purified PEGylated human glucagon-like peptide-2 reduces the severity of irradiation-induced acute radiation enteritis in rats

Nomogram Predicting Grade ≥2 Acute Radiation Enteritis in Patients With Cervical Cancer Receiving Concurrent Chemoradiotherapy

OBJECTIVE

To analyze the risk factors for grade ≥2 ARE in patients with cervical cancer receiving concurrent chemoradiotherapy.

METHODS

A total of 273 patients with cervical cancer receiving concurrent chemoradiotherapy at our hospital were retrospectively enrolled. The patients were divided into training and validation groups. Clinical parameters were analyzed using univariate analysis and multivariate logistic regression analysis. A nomogram model was established based on the independent risk factors selected using multivariate logistic regression. The areas under the receiver operating characteristic (ROC) curve, calibration curve, and decision curve analysis (DCA) were used to evaluate the nomogram. The patients were divided into low-score and high-score groups based on the scores calculated using the nomogram model and compared.

RESULTS

Malnutrition, monocyte-lymphocyte ratio ≥0.82 after radiotherapy, platelet-lymphocyte ratio <307.50 after radiotherapy, and bowelbag volume receiving at least 5 and 40 Gy were independent risk factors for grade ≥2 ARE and were incorporated into the nomogram ( P <0.05). The ROC curve, calibration curve, and DCA suggested that the nomogram had good discrimination, concordance, and net benefit in the clinical. A medium nomogram score of 146.50 points was used as the cutoff point, and the incidence of grade ≥2 ARE in the high-score group was higher than that in the low-score group ( P <0.05).

CONCLUSION

The nomogram model for grade ≥2 ARE has good predictive ability and clinical utility, and is convenient for clinicians to identify high-risk groups and develop early prevention and treatment strategies.

Therapeutic Potential of GLP-2 Analogs in Gastrointestinal Disorders: Current Knowledge, Nutritional Aspects, and Future Perspectives

PURPOSE OF REVIEW

Although Glucagon-like peptide (GLP)-1 receptor agonists have been used for almost two decades in the treatment of diabetes mellitus type 2 and, lately, in obesity, recent years have seen an increasing interest in the pharmacological agonism of other proglucagon-derived peptides, including GLP-2. Herein, we aimed to review the available evidence on the effects of GLP-2 agonism from animal and clinical studies. Furthermore, we summarize the current clinical applications of GLP-2 agonists among patients with intestinal failure associated with short bowel syndrome (SBS-IF) as well as potential future expansion of their indications to other intestinal disorders.

RECENT FINDINGS

Evidence from preclinical studies has highlighted the cellular trophic and functional beneficial actions of GLP-2 on small intestinal and colonic mucosa. Subsequently, pharmacologic agonism of GLP-2 has gathered interest for the treatment of patients with conditions pertaining to the loss of intestinal anatomical and/or functional integrity to a degree requiring parenteral support, collectively referred to as intestinal failure. GLP-2 analogs positively influence nutrient absorption in animal models and humans, although continued therapy is likely needed for sustained effects. The degradation-resistant GLP-2-analog teduglutide has received approval for the treatment of SBS-IF, in which it may decisively reduce patient dependency on parenteral support and improve quality of life. Another two longer-acting analogs, glepaglutide and apraglutide, are currently undergoing phase III clinical trials. The use of GLP-2 analogs is effective in the management of SBS-IF and may show promise in the treatment of other severe gastrointestinal disorders associated with loss of effective intestinal resorptive surface area.

Glucagon-Like Peptide-2 Modulates Enteric Paneth Cells Immune Response and Alleviates Gut Inflammation During Intravenous Fluid Infusion in Mice With a Central Catheter

Background: Glucagon-like peptide-2 (GLP-2) has protective effects on gastrointestinal functions. Our previous study found that GLP-2 could significantly reduce intestinal permeability and bacterial translocation in total parenteral nutrition (TPN) animal model. However, the effects of GLP-2 on the impairment of the intestinal Paneth cells immune function and gut inflammation during intravenous fluid infusion mainly consisted of nutritional materials is currently scattered.

Objective: The current study was aimed to investigate the efficacy of the GLP-2 in alleviating gut inflammation and modulating enteric Paneth cells immune response in parenterally fed mice and its underlying mechanisms.

Methods: Thirty-six male ICR mice underwent venous catheterization were divided into 3 groups: Chow, TPN, and TPN+GLP-2 groups. GLP-2 was administered intravenously at 60 μg/day for 5 days. The small intestine tissue and serum samples were collected on the 7th day.

Results: Compared with the TPN group, the expression of tight junction proteins occludin and claudin-1 were significantly increased in the TPN+GLP-2 group. In addition, the expression of lysozyme, sPLA2, insulin-like growth factor-1, and epithelial protection and repair genes were improved in the TPN+GLP-2 group. The levels of IL-6 and TNF-α proteins and mRNAs in the ileum tissues were remarkably reduced in the TPN+GLP-2 group, while IL-10 protein and mRNA level were elevated in the TPN+GLP-2 group (all p < 0.05). Moreover, the TPN+GLP-2 group has higher levels of serum endotoxin, D-lactic acid, and MPO than those of the TPN group.

Conclusions: GLP-2 alleviated gut inflammation and improved enteric Paneth cells immune responses through intravenous fluid infusion, possibly by improving the functioning of epithelial protection and repair, and reducing mucosal inflammatory responses.

Effects of UCMSCs Delivered through Different Transplantation Approaches on Acute Radiation Enteritis in Rats

Radiation enteritis is the most common and serious complication of abdominal or pelvic radiation therapy. Mesenchymal stem cells (MSCs), as well as cell protection agents, inhibit apoptosis and promote the proliferation of injured tissues. 3 human umbilical cords MSCs (UCMSCs) were injected into the tail vein or peritoneal cavity of a rat model of radiation enteritis. The temporary protective effect was assessed by identification of donor cells, detection of cellular immune parameters and inflammatory cytokine levels, quantitation of jejunum mucosal preservation and examination of the rat remaining life. Only the rats in the intraperitoneal injection group exhibited a few positive donor cells 7 days after transplantation. CD₄⁺/CD₈⁺ T cells, a cellular immune parameter, decreased in the abdominal exudate of intraperitoneal injection group, compared with the model-only control and tail vein groups (both P < .05). Both serum and abdominal exudate TNF-α and IL-6 levels in the intraperitoneally injected rats rapidly decreased and were significantly different from those in the model-only control and tail vein injection groups (all P < .05). Mucosal surface area and survival time increased in the intraperitoneal injection group compared with the vehicle and tail vein injection groups (all P = .000). Therefore, the administration of UCMSCs with intraperitoneal injection approach postponed death in a rat model of radiation enteritis, which was associated with reduced serum levels of proinflammatory cytokines (TNF-α, IL-6). However, UCMSCs injected via the tail vein triggered an intense cellular immune response in the serum that adversely affects their survival. This treatment failed to suppress circulating serum and abdominal exudate levels of TNF-α and IL-6 and could not provide a therapeutic benefit for prolonging life against acute radiation enteritis.

Ligustilide Prevents Radiation Enteritis by Targeting Gch1/BH4/eNOS to Improve Intestinal Ischemia

There is a high incidence of radiation enteritis (RE) after abdominal radiotherapy. The occurrence of RE seriously affects the treatment and quality of life of patients; however, its pathogenesis is complex and there are no effective drugs for its prevention or treatment. Intestinal ischemia plays an important role in the occurrence of enteritis. Previous studies have shown that targeting GTP-cyclohydrolase 1 (Gch1) to improve intestinal ischemia could be a new strategy to prevent and treat RE. A high content of the naturally occurring phthalide derivative ligustilide (LIG) has been found in the plant drug Rhizoma Ligustici Chuanxiong for the treatment of cardiovascular diseases. The purpose of this study was to evaluate the protective effects of LIG on RE. Ionizing radiation (IR) rat and endothelial cell models were used to observe and record rat body weights and stool morphologies, measure intestinal blood perfusion by laser Doppler blood flow imaging, determine the diastolic functions of mesenteric arteries, detect the levels of Gch1/BH₄/eNOS pathway-related proteins and regulatory molecules in the mesenteric arteries and endothelial cells, and predict affinity by molecular docking technology. The results showed that LIG significantly improved the body weights, loose stools, intestinal villi lengths, intestinal perfusion and vasodilatory functions of IR rats. LIG also significantly improved Gch1 protein and BH₄ levels in the mesenteric arteries and endothelial cells after IR, increased the NO content, reduced superoxide accumulation, and improved p-eNOS (Ser1177) levels in endothelial cells. LIG has good affinity for Gch1, which significantly improves its activity. These results indicate that LIG is the preferred compound for the prevention and treatment of RE by improving intestinal ischemia through the Gch1/BH₄/eNOS pathway. This study provides a theoretical basis and new research ideas for the development of new drugs for RE.

Radiation enteritis: from diagnosis to management

PURPOSE OF REVIEW

As cancer treatments improve more patients than ever are living for longer with the side effects of these treatments. Radiation enteritis is a heterogenous condition with significant morbidity. The present review aims to provide a broad overview of the condition with particular attention to the diagnosis and management of the condition.

RECENT FINDINGS

Radiation enteritis appears to be more prevalent than originally thought because of patient underreporting and a lack of clinician awareness. Patient-related and treatment-related risk factors have now been identified and should be modified where possible. Medical and surgical factors have been explored, but manipulation of the gut microbiota offers one of the most exciting recent developments in disease prevention. Diagnosis and treatment are best approached in a systematic fashion with particular attention to the exclusion of recurrent malignancy and other gastrointestinal conditions. Surgery and endoscopy both offer opportunities for management of the complications of radiation enteritis. Experimental therapies offer hope for future management of radiation enteritis but large-scale human trials are needed.

SUMMARY

Radiation enteritis is an important clinical problem, but awareness is lacking amongst patients and physicians. Clinical guidelines would allow standardised management which may improve the burden of the disease for patients.