## 3 Mitochondrial Dysfunction in AAI-Induced Kidney Diseases
### Other Types of Investigation Methods and Markers of Mitochondrial Dysfunction  
In addition to methods specific to mitochondrial activity evaluation, various other techniques are employed to assess markers involved in AAI-induced cell and tissue toxicity. These methods are summarized in Table 1.  
The aforementioned methods have proven valuable in both research and in preclinical and clinical diagnosis of AAI-induced kidney pathologies, particularly in identifying specific biomarkers. Fluorescent techniques, for instance, are highly useful in detecting AAI-induced mitochondrial dysfunction. These methods can be employed by departments such as pathological anatomy or immunology to evaluate biological samples--such as cells or biopsies--collected from affected patients. In addition to fluorescent techniques,common methods used in preclinical diagnosis include enzyme-linked immunosorbent assays (ELISA) for the detection of caspase activity, as well as biomarkers associated with oxidative stress pathways. Urinary biomarkers, like creatinine, are also frequently assessed to evaluate kidney function. A more specific, though costly, method involves the detection of mtDNA methylation. This technique is particularly valuable in the early clinical stages of kidney disease progression, offering insights into the molecular mechanisms underlying the disease. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Types of Samples** & **Imaging Investigations** & **Biochemical/ELISA** & **Western Blot** & **Molecular Biology** & **Immunology** & **Ref** \\ \hline I929–TNF-\(\alpha\) cells & TEM & Caspase 3, 8 & PARP; & cleavage of DNA & - & [24] \\  & & & MDH assay & Cytochrome c & & \\ \hline MH1C1–A23187 & Fluorescence & & Caspase 8, 9, and & & & \\  & & microscopy & - & 3 cleavage & - & - & [32] \\  & & & Cytochrome c & & & \\ \hline MDKC cells & Fluorescence & & Mitochondrial/cytosolic & Cellular & Flow cytometry: & \\ LLC-PK1 cells & microscopy & & - & fractions-cytochrome c & DNA-EtB-UV & PI & [23] \\ \hline  & HE and PAS & & WT1 & & Comet assay & \\ CD-1 mouse & TEM & Urine albumin & Middogenesis; & mtDNA copy & & \\ Mice podocyte & Immunohistochemical & and creatinine & SDHA, COXJ, actin & & mtDNA copy & \\  & staining–WT1 & Albumin influx & Cytochrome C & & number assay: & \\  & Immunofluorescent & assay & Tubulin & cytochrome B & & \\  & staining & & Actin & COX III & & \\ \hline Rats & - & caspase 3 & Cytochrome c & - & - & [20] \\ HK-2 cell & - & ATP & & & DNA: & \\  & & & & 8-oxo-dG & & \\ L02 cells & - & ATP & - & dA-ALI & & \\  & & & & (LC-MS/MS) & & \\ \hline NRK-52E cells & - & ATP & Cleaved-Caspase 3 & & q-PCR & Flow-cytometry- \\  & & & & mtDNA copy & Annexin V/PI & [2] \\  & & & & number & DCF-ROS & \\ \hline SD rats & HE; TEM & BUN; Cr; ATP & - & mtDNA & - & [12] \\ \hline  & Immunofluorescence & IL6 & TLR & & Apoptosis assay & \\  & microscopy-BrdU assay & KIM1 & TLR6 & & q-PCR & (PI; Annexin V) \\  & & NO assay & TLR9 & & Cell cycle & \\ \hline  & Inverted phase contrast & Caspase & & & & \\ NRK-52E cells & and fluorescence & H\({}_{2}\)O\({}_{2}\) and & Cleaved-caspase-3 & & & \\  & microscopy & O\({}_{2}\)– ratios & Tubulin & - & - & [25] \\ \hline Jurkat cells & - & Caspase 3 & Cytochrome c PARP & DNA fragmentation & - & [26] \\  & & & & & \\ HK-2 cells & & Inverted phase contrast & Caspase 3 & & & \\  & and fluorescence & LDH assay & & UCP2 & - & - & [33] \\  & microscopy: & MDA assay & & & & \\  & apoptosis; ROS & GSH-Px assay & & & & \\ \hline SD rats & HE; PAS; TEM & & & Cleaved-Caspase-3 & q-PCR & \\  & Confocal microscopy & & COX-I, NDUF8, & mtDNA copy & - & [30] \\  & & & PGC-1\(\alpha\) & number & & \\ \hline  & Optical and & & BUN and Cr & & & \\ NRK-2E cells & fluorescence & MDA, GSH-Px, & & & & \\ C57 BL/6 NJ mice & microscopy; TEM & & & & & \\  & HE; PAS; IHC & & & & \\  & & & & & \\ \hline BALB/c mice & HE, PAS; IHC; & & & & \\ TUNEL; TEM & BUN and Scr & LC3-I; LC3-II; Beclin-1 & - & - & [35] \\ \hline \hline \end{tabular}
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