**5. Conclusions**

Our experimental data can be summarized as Figure 7. As well as enhancing the anti-inflammatory, anti-ER stress, anti-fibrosis, anti-apoptosis, and anti-autophagy properties, anti-oxidative mechanisms also play a role in the therapeutic effect of hypoxic preconditioned MSCs on glomerulonephritis. Hypoxic preconditioning is one effective strategy to activate further intrinsic anti-oxidative defense systems by promoting the HIF-1α/VEGF signaling, Nrf2 pathway, rescue antioxidant enzymes, and increase anti-oxidative responsive element proteins.

**Figure 7.** The summary diagram is demonstrated. HMSCs prevent renal damage by suppression of pathological signals (including fibrosis, inflammation, apoptosis, and autophagy) and increase antioxidant status against oxidative stress. HMSCs reduce renal damage majorly through suppression of pathological signals.

**Author Contributions:** H.-H.C., S.-P.H., and C.-T.C. conceived the hypothesis; H.-H.C. and C.-T.C. conducted the statistical analyses for this manuscript; H.-H.C., S.-P.H., and C.-T.C. drafted the manuscript; H.-H.C., S.-P.H., and C.-T.C. contributed to discussion of the results; H.-H.C., S.-P.H., and C.-T.C. contributed to the design and conduction of the study. All the authors critically revised the drafted manuscript. All authors have read and agreed to the published version of the manuscript.

**Funding:** This work was supported by grants from the Ministry of Science and Technology (MOST 102-2320-B-003-001-MY3), National Taiwan University Hospital (Grant No. 103-N2562) and Taipei Veteran General Hospital (Grant No. VN100-02).

**Acknowledgments:** The authors would like to thank Yi-Huei Li and Jun-Tzao Huang for their dedication to the study.

**Conflicts of Interest:** All the authors declare no conflict of interest.
