Effects of granulocyte-colony stimulating factor on peritoneal defense mechanisms and bacterial translocation after administration of systemic chemotherapy in rats

Review on the effect of chemotherapy on the intestinal barrier: Epithelial permeability, mucus and bacterial translocation

Chemotherapy kills fast-growing cells including gut stem cells. This affects all components of the physical and functional intestinal barrier, i.e., the mucus layer, epithelium, and immune system. This results in an altered intestinal permeability of toxic compounds (e.g., endotoxins) as well as luminal bacterial translocation into the mucosa and central circulation. However, there is uncertainty regarding the relative contributions of the different barrier components for the development of chemotherapy-induced gut toxicity. This review present an overview of the intestinal mucosal barrier determined with various types of molecular probes and methods, and how they are affected by chemotherapy based on reported rodent and human data. We conclude that there is overwhelming evidence that chemotherapy increases bacterial translocation, and that it affects the mucosal barrier by rendering the mucosa more permeable to large permeability probes. Chemotherapy also seems to impede the intestinal mucus barrier, even though this has been less clearly evaluated from a functional standpoint but certainly plays a role in bacteria translocation. Combined, it is however difficult to outline a clear temporal or succession between the different gastrointestinal events and barrier functions, especially as chemotherapy-induced neutropenia is also involved in intestinal immunological homeostasis and bacterial translocation. A thorough characterization of this would need to include a time dependent development of neutropenia, intestinal permeability, and bacterial translocation, ideally after a range of chemotherapeutics and dosing regimens.

Design, Synthesis, and Mechanism of Dihydroartemisinin⁻Coumarin Hybrids as Potential Anti-Neuroinflammatory Agents

Cancer patients frequently suffer from cancer-related fatigue (CRF), which is a complex syndrome associated with weakness and depressed mood. Neuroinflammation is one of the major inducers of CRF. The aim of this study is to find a potential agent not only on the treatment of cancer, but also for reducing CRF level of cancer patients. In this study, total-thirty new Dihydroartemisinin-Coumarin hybrids (DCH) were designed and synthesized. The in vitro cytotoxicity against cancer cell lines (HT-29, MDA-MB-231, HCT-116, and A549) was evaluated. Simultaneously, we also tested the anti-neuroinflammatory activity of DCH. DCH could inhibit the activated microglia N9 release of NO, TNF-α, and IL-6. The docking analysis was shown that MD-2, the coreceptor of TLR4, might be one of the targets of DCH.

Comparative effects of granulocyte-colony stimulating factor and colistin-alone or in combination on burn wound healing in Acinetobacter baumannii infected mice

BACKGROUND AND OBJECTIVES

Burn wounds are one of the most important health problems all over the world because infection after burn can delay wound healing. Treating burn wounds with granulocyte-colony stimulating factor (G-CSF) is known to improve healing of injured tissue. In addition, colistin is prescribed as an effective treatment. The aim of this study was to evaluate the effect of G-CSF and colistin alone or in combination with G-CSF on wound healing of Acinetobacter baumannii (A. baumannii) infected burns.

MATERIALS AND METHODS

This study was performed between January 2016 and April 2018. Burn wounds were experimentally induced in 36 mice. The wounds were inoculated with A. baumannii. In a 7-day period, burn wounds in each group were daily treated with subcutaneous injections (0.1 ml) of saline, G-CSF, colistin, and G-CSF plus colistin. After killing the animals, the size of the wound, number of leukocytes in the skin and microbial growth were evaluated. A value of p ≤ 0.05 was considered statistically significant.

RESULTS

Wound healing in the G-CSF plus colistin group was significantly higher than the control group and the G-CSF group (P = 0.023 and P = 0.033, respectively). In G-CSF+colistin group, the number of leukocytes was higher than the control group considerably (P = 0.007). On the 7^th day of treatment, number of positive bacterial cultures in the colistin and the G-CSF plus colistin groups was lower than other groups with a significant difference.

CONCLUSION

Concurrent consumption of G-CSF and antibiotics can control burn infection and enhance the immune system towards wound healing.

Mesoporous silica nanoparticles (MSNs)-based organic/inorganic hybrid nanocarriers loading 5-Fluorouracil for the treatment of colon cancer with improved anticancer efficacy

Novel methods to improve the anticancer performance of 5-fluorouracil (5-FU) is quite necessary for clinical medicines. In the present work, we fabricated a novel type of mesoporous silica nanoparticles (MSNs)-based inorganic/organic hybrid nanoparticles covalently attached with poly(oligo(ethylene glycol) monomethyl ether methacrylate) (POEGMA) for improved stabilization and targeting peptide (RGD) for targeted delivery with the aim of improving the anticancer performance of 5-FU. Atom transfer radical polymerization (ATRP) initiator functionalized MSN (MSN-Br) was synthesized at first, which was followed by surface-initiated ATRP of water soluble OEGMA and carboxyl-containing monomer (2-succinyloxyethyl methacrylate, SEMA). Functionalization of RGD onto the hydrophilic P(OEGMA-co-SEMA) chains afforded the final hybrid nanoparticle, MSN-P(OEGMA-co-RGD). 5-FU can be effectively loaded into the meso-pores of MSN-P(OEGMA-co-RGD) (5-FU@MSN-RGD) with drug content ∼7.5wt%. And the dynamic diameter (D_h) and zeta potential (ζ) of 5-FU@MSN-RGD were determined to be 199.3±5.4nm and -8.7±0.5mV, respectively. It was demonstrated that MSN-P(OEGMA-co-RGD) exhibited improved internalization into colon cancer cells and enhanced accumulation in tumor tissues. In addition, compared with free 5-FU, 5-FU@MSN-RGD showed enhanced anticancer efficacy both in vitro and in vivo, implying promising clinical applications.

New developments in the treatment of chemotherapy-induced neutropenia: focus on balugrastim

Neutropenia and febrile neutropenia are two major complications of chemotherapy. Dose reductions, delays in treatment administration, and the use of granulocyte colony-stimulating factors are equally recommended options to preserve absolute neutrophil count in case of chemotherapy regimens bringing a risk of febrile neutropenia of 20% or higher. Recombinant granulocyte colony-stimulating factors, such as filgrastim and lenograstim, have a short elimination half-life (t_1/2) and need to be used daily, while others, like pegfilgrastim and lipegfilgrastim, are characterized by a long t_1/2 requiring only a single administration per cycle. Balugrastim is a novel long-acting recombinant granulocyte colony-stimulating factor obtained by means of a genetic fusion between recombinant human serum albumin and granulocyte colony-stimulating factor. Albumin binding increases the molecular weight and determines a high plasmatic stability leading to a t_1/2 of ~19 days. Balugrastim’s efficacy, safety, and tolerability have been assessed in four different clinical trials involving breast cancer patients treated with doxorubicin and docetaxel. Pegfilgrastim was chosen as a comparator. Balugrastim was noninferior to pegfilgrastim with regard to the reduction of mean duration of severe neutropenia during cycle 1. Moreover, both treatments were comparable in terms of efficacy and safety profile. Balugrastim was well tolerated, with the only related adverse event being mild to moderate bone pain. The aim of this review is to summarize the currently available literature data on balugrastim.

A nanomedicine-promising approach to provide an appropriate colon-targeted drug delivery system for 5-fluorouracil

Targeted drug delivery plays a significant role in disease treatment associated with the colon, affording therapeutic responses for a prolonged period of time with low side effects. Colorectal cancer is the third most common cancer in both men and women with an estimated 102,480 cases of colon cancer and 40,340 cases of rectal cancer in 2013 as reported by the American Cancer Society. In the present investigation, we developed an improved oral delivery system for existing anticancer drugs meant for colon cancer via prebiotic and probiotic approaches. The system comprises three components, namely, nanoparticles of drug coated with natural materials such as guar gum, xanthan gum (that serve as prebiotics), and probiotics. The natural gums play a dual role of protecting the drug in the gastric as well as intestinal conditions to allow its release only in the colon. In vitro results obtained from these experiments indicated the successful targeted delivery of 5-fluorouracil to the colon. Electron microscopy results demonstrated that the prepared nanoparticles were spherical in shape and 200 nm in size. The in vitro release data indicated that the maximum release occurs at pH 7.2 and 7.4 with 93% of the drug released in the presence of 4% (w/v) of rat cecal content. In vivo results conclude a practical mechanism to maintain the integrity and intactness of the intestinal/colonic microflora, in the face of a “chemical attack” by oral colon-targeted drug delivery for colon cancer treatment.

The role of IL-1β and TNF-α signaling in the genesis of cancer treatment related symptoms (CTRS): a study using cytokine receptor-deficient mice

Cytotoxic chemotherapeutic agents often induce a cluster of cancer treatment related symptoms (CTRS). The purpose of this study was to develop a mouse model of CTRS to examine the role of IL-1β and TNF-α signaling in the genesis of these symptoms. CTRS (change in wheel running activity, food intake, and body weight from baseline) were examined in wild type (WT) mice or mice lacking the TNF-α p55 (type 1) receptor (TNFR1-/-) and/or IL-1β type 1 receptor (IL-1R1-/-) injected with four doses of cyclophosphamide/Adriamycin/5-fluorouracil (CAF) at 20-day intervals. Inflammatory cytokines in blood and tissues were measured using multiplex immunoassays and quantitative RT-PCR. ANOVA was used to examine differences between genotype and/or treatment group. Kaplan-Meier analysis was used to estimate survival rate. CAF rapidly increased IL-1β and TNF-α signaling in WT mice. CAF induced acute CTRS immediately following drug injection which returned to baseline prior to the next CAF dose. Persistent CTRS were evident 3weeks after the 4th CAF dose. Acute but not persistent CTRS were associated with increased levels of IL-7, IL-9, KC, MCP-1, GCSF, and IP-10. This CAF induced inflammatory response was blunted in IL-1R1 deficient mice and absent in IL-1R1/TNFR1-deficient mice. IL-1R1-/- mice showed an identical pattern of CTRS to their WT counterparts. The assessment of CTRS in IL-1R1/TNF-R1-deficient mice was precluded by severe toxicity. Our data suggest that an important function of the IL-1β and TNF-α driven inflammatory cascade is to promote recovery following exposure to cytotoxic agents.

Inflammation and neural signaling: etiologic mechanisms of the cancer treatment-related symptom cluster

PURPOSE OF REVIEW

Cancer patients undergoing treatment with cytotoxic chemotherapeutic agents (CCAs) often experience a cluster of treatment-related symptoms, which include fatigue, loss of appetite, disturbed sleep, depressed mood, cognitive difficulties, and changes in body composition. This symptom cluster collectively referred to herein as cancer treatment-related symptoms (CTRSs) decrease quality of life, and physical and social functioning. The preclinical and clinical studies described in this review represent important progress in understanding potential underlying mechanisms of CTRS.

RECENT FINDINGS

Recent studies support a role for CCA-induced interleukin-1β (IL-1β) signaling in the cause of CTRS. CCAs may share a common ability to activate intracellular stress response pathways to trigger the synthesis, processing, and release of IL-1β from immune cells. Fatigue, sleep disturbance, and cognitive difficulties in cancer patients exposed to CCAs correlate with plasma levels of IL-6, IL-1 receptor antagonist, and soluble tumor necrosis factor receptor-I/II, surrogate markers of IL-1β-mediated central nervous system (CNS) inflammation. Additional preclinical work suggests IL-1β-mediated CNS inflammation may cause CTRS by altering hypothalamic and hippocampal functioning.

SUMMARY

Although additional research is necessary to further establish the link between CCA exposure, IL-1β-mediated inflammatory processes and CTRS, these data provide hints for future studies and therapeutic approaches in ameliorating these symptoms in cancer patients.