RESUMO
BACKGROUND: Splanchnic vein thrombosis (SVT) is an uncommon manifestation of venous thromboembolism in the splanchnic venous system, with scarce evidence surrounding its management. We assessed the efficacy and safety of direct oral anticoagulant (DOAC) to low-molecular-weight heparins (LMWH), vitamin-k antagonists (VKAs), or no anticoagulation. METHODS: We conducted a systematic review and meta-analysis with the primary efficacy outcome being complete recanalization of affected vessels and primary safety outcome being major bleeding. Meta-analysis was done using a random-effects model, with dichotomous outcomes being synthesized with odds ratios (ORs) and corresponding 95 % CIs. RESULTS: Seven non-randomized and one randomized study involving 883 participants were included for analysis. DOACs were more effective than VKAs (OR = 4.33; 95 % CI: 2.4, 7.83; n = 1 study) in non-cirrhotic patients and no anticoagulation in cirrhotic patients (OR = 3.86; 95 % CI: 1.49, 10.03; n = 3 studies). DOACs had a statistically significant reduction in major bleeding compared to observation [OR = 0.09; 95 % CI: 0.03, 0.29; n = 3 studies], LMWHs [OR = 0.13; 95 % CI: 0.03, 0.29; n = 1 study] and VKAs [OR = 0.12; 95 % CI: 0.02, 0.69; n = 2 studies] in non-cirrhotic patients. No difference in major bleeding was found between DOACs and observation, LMWH, or VKAs in cirrhotic patients. CONCLUSION: DOACs appear to be a favorable alternative to VKAs and LMWHs in non-cirrhotic patients. This avenue of research would benefit from larger studies that adjust for SVT etiologies, patient risk factors, and overall bleeding risk.
RESUMO
Endoplasmic reticulum (ER) stress is associated with acute kidney injury (AKI) caused by various mechanisms, including antibiotics, non-steroidal anti-inflammatory drugs, cisplatin, and radiocontrast. Tunicamycin (TM) is a nucleoside antibiotic that induces ER stress and is a commonly used model of AKI. 4-phenylbutyrate (4-PBA) is a chemical chaperone and histone deacetylase (HDAC) inhibitor and has been shown to protect the kidney from ER stress, apoptosis, and structural damage in a tunicamycin model of AKI. The renal protection provided by 4-PBA is attributed to its ability to prevent misfolded protein aggregation and inhibit ER stress; however, the HDAC inhibitor effects of 4-PBA have not been examined in the TM-induced model of AKI. As such, the main objective of this study was to determine if histone hyperacetylation provides any protective effects against TM-mediated AKI. The FDA-approved HDAC inhibitor vorinostat was used, as it has no ER stress inhibitory effects and therefore the histone hyperacetylation properties alone could be investigated. In vitro work demonstrated that vorinostat inhibited histone deacetylation in cultured proximal tubular cells but did not prevent ER stress or protein aggregation induced by TM. Vorinostat induced a significant increase in cell death, and exacerbated TM-mediated total cell death and apoptotic cell death. Wild type male mice were treated with TM (0.5 mg/kg, intraperitoneal injection), with or without vorinostat (50 mg/kg/day) or 4-PBA (1 g/kg/day). Mice treated with 4-PBA or vorinostat exhibited similar levels of histone hyperacetylation. Expression of the pro-apoptotic protein CHOP was induced with TM, and not inhibited by vorinostat. Further, vorinostat did not prevent any renal damage or decline in renal function caused by tunicamycin. These data suggest that the protective mechanisms found by 4-PBA are primarily due to its molecular chaperone properties, and the HDAC inhibitors used did not provide any protection against renal injury caused by ER stress.