Phenotyping Study of Cyclophosphamide 4-Hydroxylation in Malay Cancer Patients

Histological study of the role of CD34+ stem cells and mast cells in cyclophosphamide-induced thymic injury in rats and the possible attenuating role of melatonin

Cyclophosphamide (CP) is an anticancer drug that adversely affects immunity and thymus structure. Melatonin is a hormone secreted by the pineal gland. It boosts immunity and has antioxidant properties. Therefore, the present study was conducted to investigate the possible protective effect of melatonin on CP-induced changes in the rat thymus. Forty male albino rats were used and divided equally into four main groups. Group I was the control group. Group II (melatonin group) received melatonin at a dose of 10 mg/kg body weight/day by intraperitoneal injection throughout the experimental period. Group III (CP group) received 200 mg/kg body weight CP by a single intraperitoneal injection. Group IV (CP + melatonin group) received melatonin intraperitoneally at a dose of 10 mg/kg body weight/day starting 5 days prior to CP injection until the end of the experiment. All rats were euthanized 7 days after CP injection. Administration of CP in group III resulted in depletion of the cortical thymoblasts. In addition, CD34-immunopositive stained stem cells decreased and mast cell infiltration increased. Electron microscopy showed degeneration of thymoblasts and vacuolization of epithelial reticular cells. Administration of melatonin with CP in group IV showed considerable protection of thymic histology. In conclusion, melatonin may protect against CP-induced thymic injury.

Biochemical, Histological, and Ultrastructural Studies of the Protective Role of Vitamin E on Cyclophosphamide-Induced Cardiotoxicity in Male Rats

BACKGROUND

Cyclophosphamide (CP) (Cytoxan or Endoxan) is an efficient anti-tumor agent, widely used for the treatment of various neoplastic diseases. The study aimed to investigate the protective role of vitamin E (vit E) in improving cardiotoxicity in rats induced by CP.

MATERIALS AND METHODS

Forty male Wistar rats were divided randomly into four experimental groups (each consisting of ten rats); the control group was treated with saline. The other three groups were treated with vit E, CP, and the combination of vit E and CP. Serum lipid profiles, enzyme cardiac biomarkers, and cardiac tissue antioxidants were evaluated, as well as histological and ultrastructure investigations.

RESULTS

CP-treated rats showed a significant increase in serum levels of cardiac markers (troponin, CK, LDH, AST, and ALT), lipid profiles, a reduction in the antioxidant enzyme activities (CAT, SOD, and GPx), and an elevation in the level of lipid peroxidation (LPO). The increase in the levels of troponin, LDH, AST, ALP, and triglycerides is a predominant indicator of cardiac damage due to the toxic effect of CP. The biochemical changes parallel cardiac injuries such as myocardial infarction, myocarditis, and heart failure. Vitamin E played a pivotal role, as it attenuated most of these changes because of its ability to scavenge free radicals and reduce LPO. In addition, vit E was found to improve the histopathological alterations caused by CP where no evidence of damage was observed in the cardiac architecture, and the cardiac fibers had regained their normal structure with minimal hemorrhage.

CONCLUSIONS

As a result of its antioxidant activity and its stabilizing impact on the cardiomyocyte membranes, vit E is recommended as a potential candidate in decreasing the damaging effects of CP.

Advanced Microsamples: Current Applications and Considerations for Mass Spectrometry-Based Metabolic Phenotyping Pipelines

Microsamples are collections usually less than 50 µL, although all devices that we have captured as part of this review do not fit within this definition (as some can perform collections of up to 600 µL); however, they are considered microsamples that can be self-administered. These microsamples have been introduced in pre-clinical, clinical, and research settings to overcome obstacles in sampling via traditional venepuncture. However, venepuncture remains the sampling gold standard for the metabolic phenotyping of blood. This presents several challenges in metabolic phenotyping workflows: accessibility for individuals in rural and remote areas (due to the need for trained personnel), the unamenable nature to frequent sampling protocols in longitudinal research (for its invasive nature), and sample collection difficulty in the young and elderly. Furthermore, venous sample stability may be compromised when the temperate conditions necessary for cold-chain transport are beyond control. Alternatively, research utilising microsamples extends phenotyping possibilities to inborn errors of metabolism, therapeutic drug monitoring, nutrition, as well as sport and anti-doping. Although the application of microsamples in metabolic phenotyping exists, it is still in its infancy, with whole blood being overwhelmingly the primary biofluid collected through the collection method of dried blood spots. Research into the metabolic phenotyping of microsamples is limited; however, with advances in commercially available microsampling devices, common barriers such as volumetric inaccuracies and the ‘haematocrit effect’ in dried blood spot microsampling can be overcome. In this review, we provide an overview of the common uses and workflows for microsampling in metabolic phenotyping research. We discuss the advancements in technologies, highlighting key considerations and remaining knowledge gaps for the employment of microsamples in metabolic phenotyping research. This review supports the translation of research from the ‘bench to the community’.

The Nitrogen Mustards

The nitrogen mustards are powerful cytotoxic and lymphoablative agents and have been used for more than 60 years. They are employed in the treatment of cancers, sarcomas, and hematologic malignancies. Cyclophosphamide, the most versatile of the nitrogen mustards, also has a place in stem cell transplantation and the therapy of autoimmune diseases. Adverse effects caused by the nitrogen mustards on the central nervous system, kidney, heart, bladder, and gonads remain important issues. Advances in analytical techniques have facilitated the investigation of the pharmacokinetics of the nitrogen mustards, especially the oxazaphosphorines, which are prodrugs requiring metabolic activation. Enzymes involved in the metabolism of cyclophosphamide and ifosfamide are very polymorphic, but a greater understanding of the pharmacogenomic influences on their activity has not yet translated into a personalized medicine approach. In addition to damaging DNA, the nitrogen mustards can act through other mechanisms, such as antiangiogenesis and immunomodulation. The immunomodulatory properties of cyclophosphamide are an area of current exploration. In particular, cyclophosphamide decreases the number and activity of regulatory T cells, and the interaction between cyclophosphamide and the intestinal microbiome is now recognized as an important factor. New derivatives of the nitrogen mustards continue to be assessed. Oxazaphosphorine analogs have been synthesized in attempts to both improve efficacy and reduce toxicity, with varying degrees of success. Combinations of the nitrogen mustards with monoclonal antibodies and small-molecule targeted agents are being evaluated. SIGNIFICANCE STATEMENT: The nitrogen mustards are important, well-established therapeutic agents that are used to treat a variety of diseases. Their role is continuing to evolve.

Pyrroloquinoline quinone ameliorates liver injury in mice induced by cyclophosphamide

The current study aimed to investigate the potential ameliorative effects of pyrroloquinoline quinone (PQQ) on cyclophosphamide (CTX)-induced liver injury in mice. The liver injury model was established by injecting mice with CTX (80 mg/kg/day). Liver function indices, antioxidant enzyme activities, and inflammatory cytokines were evaluated. In addition, protein expression levels of the nuclear factor E2-related factor 2 (Nrf2) and nuclear factor kappa-B (NF-κB) pathways in the liver tissues were determined using western blot. The results indicated that PQQ decreased the serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and the malondialdehyde (MDA), interleukin (IL)-1β, IL-6, tumor necrosis factor-α (TNF-α) levels in the liver tissues. Moreover, PQQ enhanced the activities of oxidative stress markers to alleviate CTX induced oxidative stress. Furthermore, the expression levels of heme oxygenase-1 (HO-1), glutamate-cysteine ligase modifier subunit (GCLM), and NAD(P)H quinone oxidoreductase 1 (NQO1) were significantly increased, and the expression levels of NF-κB p50, NF-κB p65, and inhibitor of NF-κB kinase alpha (IKKα) were significantly decreased after PQQ administration, suggesting that PQQ alleviated CTX-induced liver injury via activating the Nrf2-mediated antioxidant response pathway, and inhibiting the NF-κB-mediated inflammation pathway. Therefore, PQQ can be potentially used as a dietary supplement or functional foods for alleviating the CTX-induced liver injury.