VDR/Atg3 Axis Regulates Slit Diaphragm to Tight Junction Transition via p62-Mediated Autophagy Pathway in Diabetic Nephropathy.

Foot process effacement is an important feature of early diabetic nephropathy (DN), which is closely related to the development of albuminuria. Under certain nephrotic conditions, the integrity and function of the glomerular slit diaphragm (SD) structure were impaired and replaced by the tight junction (TJ) structure, resulting in so-called SD-TJ transition, which could partially explain the effacement of foot processes at the molecular level. However, the mechanism underlying the SD-TJ transition has not been described in DN. Here, we demonstrated that impaired autophagic flux blocked p62-mediated degradation of ZO-1 (TJ protein) and promoted podocytes injury via activation of caspase3 and caspase8. Interestingly, the expression of VDR in podocytes was decreased under diabetes conditions, which impaired autophagic flux through downregulating Atg3. Of note, we also found that VDR abundance was negatively associated with impaired autophagic flux and SD-TJ transition in the glomeruli from human renal biopsy samples with DN. Furthermore, VDR activation improved autophagic flux and attenuated SD-TJ transition in the glomeruli of diabetic animal models. In conclusion, our data provided the novel insight that VDR/Atg3 axis deficiency resulted in SD-TJ transition and foot processes effacement via blocking the p62-mediated autophagy pathway in DN.

Kim-1 Targeted Extracellular Vesicles: A New Therapeutic Platform for RNAi to Treat AKI.

BACKGROUND: AKI is a significant public health problem with high morbidity and mortality. Unfortunately, no definitive treatment is available for AKI. RNA interference (RNAi) provides a new and potent method for gene therapy to tackle this issue. METHODS: We engineered red blood cell-derived extracellular vesicles (REVs) with targeting peptides and therapeutic siRNAs to treat experimental AKI in a mouse model after renal ischemia/reperfusion (I/R) injury and unilateral ureteral obstruction (UUO). Phage display identified peptides that bind to the kidney injury molecule-1 (Kim-1). RNA-sequencing (RNA-seq) characterized the transcriptome of ischemic kidney to explore potential therapeutic targets. RESULTS: REVs targeted with Kim-1-binding LTH peptide (REVLTH) efficiently homed to and accumulated at the injured tubules in kidney after I/R injury. We identified transcription factors P65 and Snai1 that drive inflammation and fibrosis as potential therapeutic targets. Taking advantage of the established REVLTH, siRNAs targeting P65 and Snai1 were efficiently delivered to ischemic kidney and consequently blocked the expression of P-p65 and Snai1 in tubules. Moreover, dual suppression of P65 and Snai1 significantly improved I/R- and UUO-induced kidney injury by alleviating tubulointerstitial inflammation and fibrosis, and potently abrogated the transition to CKD. CONCLUSIONS: A red blood cell-derived extracellular vesicle platform targeted Kim-1 in acutely injured mouse kidney and delivered siRNAs for transcription factors P65 and Snai1, alleviating inflammation and fibrosis in the tubules.

Pathogenesis of Acute Kidney Injury in Coronavirus Disease 2019.

Since the outbreak of Coronavirus Disease 2019 (COVID-19) in Wuhan, China, in December of 2019, it has rapidly become a global pandemic. Although acute respiratory disorder is the main manifestation of COVID-19, acute kidney injury (AKI) is another important extrapulmonary complication, which has a critical impact on the prognosis and mortality of patients. Current understanding about the exact pathogenesis of AKI in COVID-19 is unclear. Several studies have suggested that intrarenal, pre-renal and post-renal factors mediated collaboratively by direct virus attack, overloaded immune responses, drugs, sepsis, coagulation dysfunction, and underlying diseases may all be involved in the pathogenesis of AKI. This article reviews the current understanding of the pathogenesis of AKI in COVID-19.

Acute Kidney Injury in the 2019 Novel Coronavirus Disease.

BACKGROUND: The 2019 novel coronavirus disease (CO-VID-19) is a newly defined serious infectious disease caused by the SARS-CoV-2 virus. The epidemic started in Wuhan, China, in December of 2019 and quickly spread to over 200 countries. It has affected 4,258,666 people, with 294,190 deaths worldwide by May 15, 2020. COVID-19 is characterized by acute respiratory disease, with 80% of patients presenting mild like flu-like symptoms; however, 20% of patients may have a severe or critical clinical presentation, which likely causes multiple organ injuries (e.g., kidney, heart, blood, and nervous system). Among them, acute kidney injury (AKI) is a critical complication due to its high incidence and mortality rate. Here we present a review of the current understanding of AKI in COVID-19. SUMMARY: CO-VID-19 is a catastrophic contagious disease caused by the coronavirus, and the AKI induced by COVID-19 significantly increases the mortality rate. In this review, we summarize the clinical characteristics of COVID-19 induced AKI by focusing on its epidemiology, pathogenesis, clinical diagnosis, and treatment. KEY MESSAGES: Multiple studies have shown that COVID-19 may involve the kidneys and cause AKI. This article reviews the characteristics of COVID-19-induced AKI largely based on up-to-date studies in the hope that it will be helpful in the current global fight against and treatment of COVID-19.

Anti-HIV-1 activities of extracts and phenolics from Smilax china L.

Four extracts (EtOH, CHCl3, EtOAc, and BuOH) and five phenolics (dihydrokaempferol (1), resveratrol (2), kaempferol-7-O-ß-D-glucoside (3), dihydrokaempferol-3-O-α-L-rhamnoside (4), oxyresveratrol (5)) from Smilax china L. was evaluated for anti-HIV-1 activities and cytotoxicity activities in vitro. All these extracts and phenolics showed lower or no cytotoxicity at a concentration ranged from 0.8 µg/mL to 100 µg/mL, but some showed potential anti-HIV-1 activities, that is, BuOH extract and compound 2 showed higher anti-HIV-1 activities than other extracts and compounds in the tested concentrations. EtOAc extract and compound 1 and 3 showed moderate anti-HIV-1 activities at a concentration higher than 4 µg/mL. In the end, the structure-activity relationship of four extracts and five phenolics was discussed.

SELDI-TOF MS combined with magnetic beads for detecting serum protein biomarkers and establishment of a boosting decision tree model for diagnosis of pancreatic cancer.

AIM: New technologies for the early detection of pancreatic cancer (PC) are urgently needed. The aim of the present study was to screen for the potential protein biomarkers in serum using proteomic fingerprint technology. METHODS: Magnetic beads combined with surface-enhanced laser desorption/ionization (SELDI) TOF MS were used to profile and compare the protein spectra of serum samples from 85 patients with pancreatic cancer, 50 patients with acute-on-chronic pancreatitis and 98 healthy blood donors. Proteomic patterns associated with pancreatic cancer were identified with Biomarker Patterns Software. RESULTS: A total of 37 differential m/z peaks were identified that were related to PC (P<0.01). A tree model of biomarkers was constructed with the software based on the three biomarkers (7762 Da, 8560 Da, 11654 Da), this showing excellent separation between pancreatic cancer and non-cancer., with a sensitivity of 93.3% and a specificity of 95.6%. Blind test data showed a sensitivity of 88% and a specificity of 91.4%. CONCLUSIONS: The results suggested that serum biomarkers for pancreatic cancer can be detected using SELDI-TOF-MS combined with magnetic beads. Application of combined biomarkers may provide a powerful and reliable diagnostic method for pancreatic cancer with a high sensitivity and specificity.