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Background/Aims: Renal ischemia-reperfusion injury (IRI) is a common consequence of acute kidney injury. Nicotinamide adenine dinucleotide phosphate (NADPH), which is derived from the pentose phosphate pathway, is essential for the proper functioning of essential redox and antioxidant defense systems. Previous studies have indicated that NADPH is responsible for protecting the brain from ischemic injury. The goal of this study was to analyze the protective function of NADPH in renal IRI. Methods: The IRI animal model was generated through a midline laparotomy surgery that clamped both sides of the renal pedicles for 40 min to induce renal ischemia. The in vitro model was generated by removing oxygen and glucose from human kidney epithelial cells (HK-2 cells), followed by reoxygenation to imitate IRI. Renal function and histopathological changes were observed and evaluated. Additionally, malondialdehyde and glutathione levels were determined in renal tissue homogenate as indicators of oxidative stress. ROS production in cells was determined by DHE staining. Protein biomarker expression was evaluated by western blot, apoptosis was analyzed by TUNEL staining, and p65 nuclear translocation was visualized by immunofluorescence. Results: Our data indicated that NADPH safeguarded the kidneys from histological and functional damage, and significantly reduce cell injury along with preventing potential increases in blood urea nitrogen and creatinine levels. Furthermore, we observed that NADPH increased glutathione levels, while reducing levels of malondialdehyde and reactive oxygen species. Additionally, our results suggested that NADPH treatment may alleviate IRI-induced apoptosis and inflammation. Conclusion: NADPH treatment may protect against renal IRI and should be further developed as a new treatment for acute kidney injury.

// Yun-fang Zhen 1, * , Song-tao Li 2, * , Yun-rong Zhu 3, * , Xiao-dong Wang 1 , Xiao-zhong Zhou 2 , Lun-qing Zhu 1 1 The Center of Diagnosis and Treatment for Children’s Bone Diseases, The Children’s Hospital Affiliated to Soochow University, Suzhou, China 2 The Department of Orthopedics, The Second Affiliated Hospital of Soochow University, Suzhou, China 3 Department of Orthopedics, The Affiliated Jiangyin Hospital of Medical College of Southeast University, Jiangyin, China * These authors have contributed equally to this work Correspondence to: Lun-qing Zhu, email: zhulunqingszgk@163.com Xiao-dong Wang, email: xiaodongwangsz@163.com Xiao-zhong Zhou, email: zhouxiaozhongorth@163.com Keywords: osteosarcoma (OS), salinomycin, DNA-PKcs, microRNA-101, autophagy Received: September 09, 2016 Accepted: September 26, 2016 Published: October 17, 2016 ABSTRACT Malignant osteosarcoma (OS) is still a deadly disease for many affected patients. The search for the novel anti-OS agent is extremely urgent and important. Our previous study has proposed that salinomycin is a novel anti-OS agent. Here we characterized DNA-dependent protein kinase catalytic subunit (DNA-PKcs) as a primary salinomycin resistance factor in OS cells. DNA-PKcs inhibitors (NU7026, NU7441 and LY294002) or DNA-PKcs shRNA knockdown dramatically potentiated salinomycin-induced death and apoptosis of OS cells (U2OS and MG-63 lines). Further, forced-expression of microRNA-101 (“miR-101”) downregulated DNA-PKcs and augmented salinomycin’s cytotoxicity against OS cells. Reversely, over-expression of DNA-PKcs in OS cells inhibited salinomycin’s lethality. For the mechanism study, we show that DNA-PKcs is required for salinomycin-induced pro-survival autophagy activation. DNA-PKcs inhibition (by NU7441), shRNA knockdown or miR-101 expression inhibited salinomycin-induced Beclin-1 expression and autophagy induction. Meanwhile, knockdown of Beclin-1 by shRNA significantly sensitized salinomycin-induced OS cell lethality. In vivo , salinomycin administration suppressed U2OS xenograft tumor growth in severe combined immuno-deficient (SCID) mice, and its anti-tumor activity was dramatically potentiated with co-administration of the DNA-PKcs inhibitor NU7026. Together, these results suggest that DNA-PKcs could be a primary resistance factor of salinomycin in OS cells. DNA-PKcs inhibition or silence may thus significantly increase salinomycin’s sensitivity in OS cells.

Dexamethasone (Dex) causes osteoblast cell injuries. In the present research, we tested the potential effect of SC79, a novel and specific Akt activator, against Dex in osteoblasts. In primary murine osteoblasts and osteoblastic MC3T3-E1 cells, pretreatment with SC79 significantly attenuated Dex-induced cell death. Further, Dex-induced mitochondrial permeability transition pore (mPTP) opening, cytochrome C release and apoptosis activation were dramatically alleviated with SC79 pretreatment in above cells. At the molecular level, SC79 activated Akt, which was indispensable for subsequent osteoblast protection against Dex. Akt inhibitors (LY294002, perifosine and MK-2206) blocked SC79-induced Akt activation and abolished its anti-Dex actions in osteoblasts. Further, SC79 activated Akt downstream Nrf2 (NF-E2-related factor 2) signaling and attenuated Dex-induced oxidative stress in osteoblasts. Nrf2 shRNA knockdown or S40T mutation almost reversed SC79-mediated anti-oxidant and cytoprotective activities in osteoblasts. Together, these results suggest that SC79 activates Akt-Nrf2 signaling to protect osteoblasts from Dex.

To investigate the mechanism of Longchang Granule in the treatment of benign prostatic hyperplasia.Rat models of prostate hyperplasia were made by castration and testosterone propionate injection. After treated respectively with Longchang Granule and Longbishu by gastrogavage for 30 days, all the model rats were killed and their prostate glands harvested for the measurement of the wet weight and detection of the expression of bax in the prostatic hyperplastic tissues by RV 2-step method.The wet weight of the prostate was (0.61 +/- 0.03) g in the blank control group, (0.95 +/- 0.04) g in the model group, (0.73 +/- 0.02) g in the Longbishu group, (0.80 +/- 0.05) g in the low-dose Longchang group, (0.78 +/- 0.07) g in the medium-dose Longchang group and (0.68 +/- 0.03) g in the high-dose Longchang group, with significant differences between the model and the intervention groups (P0.05). The prostate indexes in the above groups were 0.143 +/- 0.006, 0.226 +/- 0.008, 0.172 +/- 0.004, 0.199 +/- 0.012, 0.181 +/- 0.010 and 0.168 +/- 0.003, respectively, and the expressions of bax by mean optical density were 0.226 +/- 0.010, 0.184 +/- 0.005, 0.206 +/- 0.015, 0.199 +/- 0.001, 0.202 +/- 0.003 and 0.211 +/- 0.003, respectively, both with significant differences between the model and the intervention groups (P0.05).Longchang Granule can effectively reduce the wet weight of the prostate and alleviate its pathological changes in BPH rats, the mechanism of which may be associated with its effect of upregulating the expression of bax and accelerating cell apoptosis in the prostate tissues.