## 4 Discussion  
We investigated the combined effect of NIR with IRE treatment, so-called NIRE, to enhance apoptosis in murine gastric tissue. Utilizing an energy density of 3 J/cm\({}^{2}\) for NIR, based on prior research [19], we observed that NIR influenced the electrostatic properties of the tissue. This was evident from the altered impedance after IRE and NIRE treatment (Figure 1B). While, it is established that NIR modifies the optical properties of tissue [31], limited studies address its impact on tissue's electrical characteristics. One explanation for  
Figure 5: Evaluation of gene expression in apoptotic signaling pathways. (**A**) Western blot analysis 12 h after IRE treatment. (**B**) Quantitative analysis of protein expression. It indicated significantly higher levels of BCL, p21, and SOD2 in NIRE samples compared to those in IRE samples. Data are presented as the mean \(\pm\) standard deviation (n = 3). Statistical significance was determined using a two-tailed paired Student’s \(t\)-test (* \(p\) < 0.05) and an ANOVA followed by [PERSON]’s HSD test (* \(p\) < 0.05; **\(p\) < 0.01; *** \(p\) < 0.001). the observed impedance shift could be the temperature-dependent resistivity principle. As the tissue absorbs NIR, it may undergo temperature changes, potentially altering its electrical attributes. Despite the thermal effects suggested by another study [32], temperature may play a minor role in influencing electrical impedance. Simultaneously, NIR's potential to change the tissue's dielectric properties could subsequently affect its electrical impedance. Supporting this, our prior in vitro research demonstrated that NIR irradiation can alter electrical capacitance and conductivity [19]. Additionally, our findings reveal that NIR's effects on electrical properties are mediated through NIRE. Histopathological analysis showed that NIRE treatment led to notably more apoptosis than IRE alone (Figure 2C), suggesting that NIR could enhance tissue's sensitivity to IRE by altering conductivity. While the TUNEL assay offers insights into DNA fragmentation during apoptosis [33], our H & E analysis revealed consistent outcomes across various tissue layers with IRE and NIRE treatments. However, the WB method highlighted a difference in protein expression linked to apoptosis. WB, a widely recognized molecular biology technique, was employed to identify protein variations induced by IRE or NIRE, especially focusing on apoptotic signals. Apoptosis, a programmed cell death, typically manifests through unique signaling pathways [34]. Bcl-xl, associated with the BCL2-like 1 gene, acts as an anti-apoptotic protein by preventing mitochondrial content release, such as cytochrome c [35]. The p21 protein regulates cell cycle progression [36], while SOD2 facilitates electron transport activity, converting oxidative phosphorylation byproducts to hydrogen peroxide and diatomic oxygen [37]. Among these proteins, SOD2 expression was observed to increase after IRE treatment [38; 39]. In addition, p21 protein expression was enhanced by IRE treatment [40] by using Western blotting. However, Bcl-xl expression was reduced by IRE treatment [41]. In our experiment, Bcl-xl expression decreased with IRE but increased further with NIRE treatment compared to IRE. Bcl-xl, a member of the Bcl-2 family, is vital in apoptosis regulation [42], and its altered expression in many cancers helps evade apoptosis [43]. Conversely, the activation of the BCL2-associated x protein (BAX) and BCL2-antagonist-killer (BAK) can initiate apoptotic events through cytochrome c release [44]. The enhanced Bcl-xl expression in NIRE-treated samples, compared to controls, suggests a potential increase in apoptotic signals. Further studies on the expression of Bcl-xl due to NIRE treatment are needed. Moreover, p21 activation was more prominent in NIRE-than IRE-treated samples, aligning with previous findings that link p21 activation to DNA damage and subsequent apoptosis [45; 46; 47].