Iron-related Genes and Proteins Involved in Iron Homeostasis in Animal Models of Allergic Asthma: A Systematic Review.

The involvement of the immune oxidative stress response in the pathophysiology and pathogenesis of allergic asthma is well documented. However, reports on the role of iron homeostasis in allergic asthma is scarce. Therefore, this study aims to identify iron-related genes and proteins in mouse models of allergic asthma. Related articles were identified from SCOPUS and Web of Science databases. The article search was limited to publications in English, within a 10-year period (2014 - 2023, up to 16 August 2023) and original/research papers. All identified articles were screened for eligibility using the inclusion and exclusion criteria. All eligible articles were quality appraised prior to data extraction. Five studies were selected for data extraction. Based on the extracted data, three themes and seven subthemes related to iron homeostasis were identified. The type of samples and analytical methods used were also identified. In conclusion, our study elucidates that iron-related proteins are regulated in animal models of allergic asthma. However, the currently available data do not allow us to conclude whether the disease model resulted in iron accumulation or depletion. Therefore, further studies with other related markers should be conducted.

Inflammation and oxidative stress impair preimplantation embryonic morphogenesis in allergic asthma model.

The incidence of allergic asthma has been increasing worldwide in recent decades. Also, an increasing number of women are suffering from poor pregnancy outcome. However, the causal relationship between allergic asthma and embryonic growth in terms of cell morphogenesis has not been well elucidated. Here, we investigated the impact of allergic asthma on the morphogenesis of preimplantation embryos. Twenty-four female BALB/c were randomly divided into control (PBS), 50-µg (OVA1), 100-µg (OVA2) and 150-µg (OVA3). On Days-0 and -14, mice were induced intraperitoneally (i.p) with ovalbumin (OVA). On Days-21 until -23, mice were challenged with OVA via intranasal instillation (i.n). Control animals were sensitized and challenged with PBS. At the end of treatment (Day-25), 2-cell embryos were retrieved and cultured in vitro until the blastocysts hatched. Results showed reduced number of preimplantation embryos at all developing stages in all treated groups (p ≤ 0.0001). Uneven blastomere size, partial compaction- and cavitation-activity, low formation of trophectoderm (TE), as well as cell fragmentation were noted in all the treated groups. Maternal serum interleukin (IL)-4, immunoglobulin (Ig)-E and 8-hydroxydeoxyguanosine (8-OHdG) were notably high (p ≤ 0.0001, p ≤ 0.01) in contrast with low total antioxidant capacity (TAOC) (p ≤ 0.0001). Our findings indicated that OVA-induced allergic asthma had compromised cell morphogenesis through reduced blastomere cleavage division, partial compaction and cavitation-activity, impairment of TE production, and cell fragmentation leading to embryonic cell death via OS mechanism.

Ovalbumin causes impairment of preimplantation embryonic growth in asthma-induced mice.

Insufficient experimental studies have reported the effect of ovalbumin (OVA) as an allergen towards embryonic growth in asthma mouse model. The impact of 10 µg/200 µL OVA on maternal inflammatory and oxidative stress (OS) responses, and preimplantation embryonic development was investigated in this study. We first established OVA-induced asthma mouse model, and following superovulation, mated the females and challenged them with Methacholine (Mch) test. Upon embryo retrieval, only those with the highest implantation potential were cultured in vitro. Significant reduction in the number of embryos at each preimplantation stage was noted in the treated group. Uneven sized blastomeres at 2-, 4- and 8-cell stages were also evident in this group. Embryo fragmentation was significant at only 2-, 4- and 8-cell stages. We also found that OVA tended to raise maternal inflammatory and OS biomarker levels as well as to cause inappropriate levels of pregnancy hormones progesterone (P4) and estrogen (E2) although insignificant. The combined results indicate that 10 µg/200 µL OVA had altered both quality and quantity of the embryos in asthma mouse model although its effect on pregnancy hormones, inflammatory and OS responses were non-pathological.