## 3 Discussion  
In this study, we propose that exogenous administration of H\({}_{2}\)S can effectively elevate endogenous H\({}_{2}\)S levels, although the precise underling mechanism remains unknown, and is yet to be determined. It is hypothesized that this elevation in H\({}_{2}\)S levels may directly influence the expression and activity of antioxidant and detoxification genes/mechanisms in individuals with low ferritin levels, as well as potentially in other conditions characterized by oxidative stress imbalance. The endogenous cellular signaling and potent reducing properties of H\({}_{2}\)S make it a highly promising candidate for protective applications. H\({}_{2}\)S can easily interact with disulfide bonds (RSSSR) and effectively scavenge ROS [3; 21]. Furthermore, H\({}_{2}\)S has been shown to have the ability to directly scavenge peroxynnitrite and reduce peroxynnitrite toxicity in various cellular modules [21]. The effect of H\({}_{2}\)S on antioxidant profile and cellular redox has already been highlighted [7; 22]. Notably, H\({}_{2}\)S directly modifies thioredoxin and enhances its activity, thereby causing a protective effect to the cells against oxidative damage [23]. These innovative strategies hold promising potential for the  
Figure 5: Total antioxidant capacity in individuals with low and normal ferritin status after environmental H\({}_{2}\)S exposure. The values are reported as the mean \(\pm\) standard deviation. The symbol “#” indicates a significant difference at \(p<0.05\) when comparing the low-ferritin group who were not exposed to H\({}_{2}\)S. The symbol “**” indicates a significant difference at \(p<0.05\) when comparing the normal ferritin group to the low-ferritin group in group A, which had not been exposed to H\({}_{2}\)S. The symbol “***” indicates a significant difference at \(p<0.05\) when comparing the low-ferritin group B to the low-ferritin group A. Group A refers to individuals who were not exposed to environmental H\({}_{2}\)S, while group B refers to individuals who were exposed to environmental H\({}_{2}\)S.  
development of therapies approaches targeting oxidative stress-related pathologies associated with IDA. Additionally, it is important to acknowledge that iron-related oxidative stress can catalyze the conversion of superoxide and hydrogen peroxide into more potent oxidants through Fenton-type reactions [24]. However, the failure to effectively neutralize these ROS, which are produced during normal metabolic processes, can lead to the damage of cellular proteins, lipids and nucleic acids [25] and thereby the development of various chronic diseases [25]. Endogenous antioxidant plays a major role in protecting the human body against damage caused by oxidative stress and maintaining redox homeostasis [26]. Therefore, enhancing the capacity of endogenous antioxidant capacity presents a valuable approach for managing diseases associated with oxidative stress. H2S is a well-known endogenous antioxidant modulator. In this study, H2S exposure from sulfur springs were employed to examine the potential correlation between H2S levels and antioxidant effects in individuals with low ferritin levels who exhibit elevated levels of ROS. The results demonstrated a significant elevation in oxidative stress and a reduction in antioxidant-H2S levels among individuals with low ferritin status. However, following exposure to environmental H2S, both endogenous H2S and antioxidant levels exhibited an increase. A previous study reported that exogenous H2S administration increased the expression of all three H2S producing enzymes in vivo [27]. Similarly, pretreatment with the H2S chemical donor NaHS, exhibited a concentration-dependent increase in CBS levels. Notably, a concentration of 50 \(\upmu\)M NaHS treatment was found to increase the activity of CSE relative to CBS in vitro experiment [28]. The production of antioxidants in the body encompasses both enzymatic and non-enzymatic mechanisms. Enzymatic antioxidants include superoxide dismutase, catalase, and glutathione peroxidase [26].