Amifostine-Loaded Nanocarrier Traverses the Blood-Brain Barrier and Prevents Radiation-Induced Brain Injury

Maintained homeostasis: LGYD facilitated the restoration of ISCs following radiation exposure by activating Hes1

BACKGROUND

Radiation-induced Intestinal Injury (RIII) affects quality of life in radiotherapy patients; Liangxue Guyuan Yishen Decoction (LGYD) offers protection but requires further study on its mechanism.

PURPOSE

The aim of this study was to investigate the heterogeneity of cellular responses in the intestine at a single-cell level following radiation and LGYD treatment.

STUDY DESIGN

This study's design includes in vivo and in vitro assessments to evaluate LGYD's effects on intestinal cells post-radiation, targeting survival, recovery, and molecular pathways.

METHODS

Mice were categorized into four groups: LGYD group, NC group, IR group, and Am group. Each group received daily drug administrations. All groups, except for the NC group, were subjected to a single whole-body irradiation at a dose rate of 70 R/min with a source-to-skin distance of 250 cm. Subsequent experiments were conducted following the irradiation, which led to severe survival impairments in the mice.

RESULTS

Our findings demonstrate that LGYD intervention substantially improves survival rates following lethal doses (8.5 Gy, 70R/min) of whole-body irradiation. Moreover, LGYD expedites the recovery period for intestinal injury on the fifth day after radiation by promoting repair mechanisms within intestinal tissue, with particular focus on mitigating intestinal stem cells (ISCs) damage and immune disorders. Through both in vivo and in vitro experiments, we have discovered that LGYD effectively treats RIII by activating Hes1 transcription factor activity through its key active ingredients in drug-containing serum. This activation further upregulates the downstream Stat3 and Akt gene, thereby facilitating repair processes within intestinal stem cells.

CONCLUSION

In this study, we discovered that LGYD can enhance the downstream expression and phosphorylation pathways of Stat3 and Akt by upregulating the expression of Hes1 gene following high-dose radiation exposure.

Metal-organic framework-edaravone nanoparticles for radiotherapy-induced brain injury treatment

Cranial radiotherapy may cause damage to normal brain tissues and induce cognitive dysfunction, so developing an effective strategy to prevent radiotherapy-induced brain injury is essential. Metal-organic frameworks (MOFs) can be used as vectors for the delivery of neuroprotective drugs due to their high drug loading capacity and low toxicity. In this study, we synthesized MIL-53(Cr) nanoparticles, which were used to deliver edaravone, and modified the surface of the nanoparticles with polyethylene glycol and Angiopep-2 (EDA@MIL-53(Cr)-P/A) to improve their oral bioavailability and ability to cross the blood-brain barrier (BBB). We confirmed that MIL-53(Cr)-P/A nanoparticles could achieve the sustained release of edaravone and enhance its ability to cross the BBB. The results of in vitro experiments showed that EDA@MIL-53(Cr)-P/A could exert radioprotective effects on HT22 and BV2 cells. We also demonstrated that EDA@MIL-53(Cr)-P/A could alleviate brain injury and cognitive dysfunction in mice receiving whole-brain irradiation. Mechanistically, EDA@MIL-53(Cr)-P/A alleviated irradiation-induced brain damage by inhibiting oxidative stress, DNA damage, apoptosis and inflammatory reactions. This study provides a new strategy for the protection against radiotherapy-induced brain injury.

Radiation-Induced Brain Injury: Mechanistic Insights and the Promise of Gut-Brain Axis Therapies

Radiation therapy is widely recognized as an efficacious modality for treating neoplasms located within the craniofacial region. Nevertheless, this approach is not devoid of risks, predominantly concerning potential harm to the neural structures. Adverse effects may encompass focal cerebral necrosis, cognitive function compromise, cerebrovascular pathology, spinal cord injury, and detriment to the neural fibers constituting the brachial plexus. With increasing survival rates among oncology patients, evaluating post-treatment quality of life has become crucial in assessing the benefits of radiation therapy. Consequently, it is imperative to investigate therapeutic strategies to mitigate cerebral complications from radiation exposure. Current management of radiation-induced cerebral damage involves corticosteroids and bevacizumab, with preclinical research on antioxidants and thalidomide. Despite these efforts, an optimal treatment remains elusive. Recent studies suggest the gut microbiota's involvement in neurologic pathologies. This review aims to discuss the causes and existing treatments for radiation-induced cerebral injury and explore gut microbiota modulation as a potential therapeutic strategy.

Isoquercitrin Loaded PEGylated Long Circulating Liposomes Improve Bone Mass and Reduce Oxidative Stress After Osteoporosis

Osteoporosis has increasingly become a major public health concern because of its associated heightened risk of bone fragility and fractures. In order to avoid the adverse risk of hormone therapy, scientists have considered isoquercitrin (IQ) as a natural phytoestrogen to potentially prevent osteoporosis. However, IQ has poor solubility and bioavailability which culminates in rapid elimination of phytoestrogen. Herein, this study sought to solve limited applications of IQ by preparing IQ-loaded PEGylated long circulating liposomes (IQ-Lips) via thin-film hydration method. After appropriate characterization using zeta-potential, polydispersed index (PDI), particle size and entrapment efficiency (EE), IQ-Lips were applied to ovariectomized rat models to evaluate their effect on osteoporosis. The results showed that the prepared IQ-Lips exhibited smaller sized nanoparticles (125.35 ± 4.50 nm), excellent PDI (0.244 ± 0.001) and zeta-potential (-28.64 ± 0.71 mV) with stable property and higher EE (92.10 ± 0.32%). Importantly, administration of IQ-Lips through oral route increased aqueous solvability, bioavailability and circulation time of IQ. Moreover, the IQ-Lips could increase bone microstructural densities and bone mass, as well as reduce oxidative stress in ovariectomized rat models. Altogether, the IQ-Lips may serve as a novel avenue to potentially prolong the circulation of IQ in the body and improve the bioavailability of IQ for treatment of osteoporosis.

Amifostine loaded lipid-calcium carbonate nanoparticles as an oral drug delivery system for radiation protection

Amifostine (AMF) as the first-line radiation protection drug, usually suffered from low compliance and short half-life upon clinical applications. The development of oral drug delivery system (DDS) for AMF is a promising solution. However, the inherent shortages of AMF present significant challenges in the design of suitable oral DDS. Here in this study, we utilized the ability of calcium ions to bind with AMF and prepared AMF loaded calcium carbonate (CC) core, CC/AMF, using phase transferred coprecipitation method. We further modified the CC/AMF using phospholipids to prepare AMF loaded lipid-calcium carbonate (LCC) hybrid nanoparticles (LCC/AMF) via a thin-film dispersion method. LCC/AMF combines the oral advantages of lipid nanoparticles with the drug-loading capabilities of CC, which was shown as uniform nano-sized formulation with decent stability in aqueous solution. With favorable intestinal transport and absorption effects, it effectively enhances the in vivo radiation protection efficacy of AMF through oral administration. More importantly, we further investigated the cellular accumulation profile and intracellular transport mechanism of LCC/AMF using MDCK and Caco-2 cell lines as models. This research not only alters the current administration method of AMF to enhance its convenience and compliance, but also provides insights and guidance for the development of more suitable oral DDS for AMF in the future.

Hyperbaric Oxygen Therapy as an Alternative Therapeutic Option for Radiation-Induced Necrosis Following Radiotherapy for Intracranial Pathologies

BACKGROUND

Radiotherapy (RT) is a feasible adjuvant therapeutic option for managing intracranial pathologies. One of the late complications of RT that frequently develops within months following RT is radiation necrosis (RN). Corticosteroids are the first-line therapeutic option for RNs; however, in case of unfavorable outcomes or intolerability, several other options, including bevacizumab, laser interstitial thermal therapy, surgery, and hyperbaric oxygen therapy (HBOT). Our goal was to investigate the feasibility and efficacy of the application of HBOT in RNs following RT and help physicians make decisions based on the latest data in the literature.

METHODS

We provide a comprehensive review of the literature on the current issues of utilization of HBOT in RNs.

RESULTS

We included 11 studies with a total of 46 patients who underwent HBOT. Most of the cases were diagnosed with brain tumors or arteriovenous malformations. Improvement was achieved in most of the cases.

DISCUSSION

HBOT is a noninvasive therapeutic intervention that can play a role in adjuvant therapy concurrent with RT and chemotherapy and treating RNs. HBOT resolves the RN through 3 mechanisms, including angiogenesis, anti-inflammatory modulation, and cellular repair. Previous studies demonstrated that HBOT is a feasible and well-tolerated therapeutic option that has shown promising results in improving clinical and radiological outcomes in intracranial RNs. Complications of HBOT are usually mild and reversible.

CONCLUSIONS

HBOT is a feasible and effective therapeutic option in steroid-refractory RNs and is associated with favorable outcomes and a low rate of side effects.