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Background: Ginseng is believed to have antitumor activity. Autophagy is largely a prosurvival cellular process that is activated in response to cellular stressors, including cytotoxic chemotherapy; therefore, agents that inhibit autophagy can be used as chemosensitizers in cancer treatment. We examined the ability of Korean Red Ginseng extract (RGE) to prevent autophagic flux and to make hepatocellular carcinoma (HCC) cells become more sensitive to doxorubicin. Methods: The cytotoxic effects of total RGE or its saponin fraction (RGS) on HCC cells were examined by the lactate dehydrogenase assay in a dose- or time-dependent manner. The effect of RGE or RGS on autophagy was measured by analyzing microtubule-associated protein 1A/1B-light chain (LC)3-II expression and LC3 puncta formation in HCC cells. Late-stage autophagy suppression was tested using tandem-labeled green fluorescent protein (GFP)–monomeric red fluorescent protein (mRFP)–LC3. Results: RGE markedly increased the amount of LC3-II, but green and red puncta in tandem-labeled GFP–mRFP–LC3 remained colocalized over time, indicating that RGE inhibited autophagy at a late stage. Suppression of autophagy through knockdown of key ATG genes increased doxorubicin-induced cell death, suggesting that autophagy induced by doxorubicin has a protective function in HCC. Finally, RGE and RGS markedly sensitized HCC cells, (but not normal liver cells), to doxorubicin-induced cell death. Conclusion: Our data suggest that inhibition of late-stage autophagic flux by RGE is important for its potentiation of doxorubicin-induced cancer cell death. Therapy combining RGE with doxorubicin could serve as an effective strategy in the treatment of HCC. Keywords: autophagic flux, cell death, ginseng extract

Nicotinamide phosphoribosyltransferase (NAMPT) is the rate-limiting enzyme in the nicotinamide adenine dinucleotide (NAD+) salvage pathway and plays a crucial role in the maintenance of the NAD+ pool during inflammation. Considering that macrophages are essential for tissue homeostasis and inflammation, we sought to examine the functional impact of NAMPT in inflammatory macrophages, particularly in the context of inflammatory bowel disease (IBD). In this study, we show that mice with NAMPT deletion within the myeloid compartment (Namptf/fLysMCre+/-, Nampt mKO) have more pronounced colitis with lower survival rates, as well as numerous uncleared apoptotic corpses within the mucosal layer. Nampt-deficient macrophages exhibit reduced phagocytic activity due to insufficient NAD+ abundance, which is required to produce NADPH for the oxidative burst. Nicotinamide mononucleotide (NMN) treatment rescues NADPH levels in Nampt mKO macrophages and sustains superoxide generation via NADPH oxidase. Consequently, Nampt mKO mice fail to clear dead cells during tissue repair, leading to substantially prolonged chronic colitis. Moreover, systemic administration of NMN, to supply NAD+, effectively suppresses the disease severity of DSS-induced colitis. Collectively, our findings suggest that activation of the NAMPT-dependent NAD+ biosynthetic pathway, via NMN administration, is a potential therapeutic strategy for managing inflammatory diseases., Graphical abstract Image 1, Highlights • The depletion of NAMPT in macrophages promotes susceptibility to colitis. • NAMPT-mediated phagocytic activity is required for engulfing dead cells, leading to tissue repair. • NMN administration mitigates colitis severity. • NAMPT-dependent NAD+ biosynthetic pathway activation may treat inflammatory disease.

Objective: We aimed to develop an optimal protocol for failed mechanical thrombectomy (MT) in cases of emergent large vessel occlusion (ELVO) with intracranial atherosclerosis (ICAS). Methods: A total of 117 patients without underlying heart disease who were not taking antiplatelet drugs had early reocclusion during MT for ELVO due to ICAS. They were divided into the following 3 groups according to rescue treatment methods: 1) Combined intravenous (IV) + intra-arterial (IA) tirofiban group (n = 48), emergent percutaneous transluminal angioplasty (PTA) and intracranial stenting (ICS) followed by IA injection of tirofiban and a continuous IV tirofiban infusion for 8 h; 2) IA tirofiban group (n = 33), only IA 0.5–1.0 mg tirofiban infusion for 5 min regardless of PTA or ICS; and 3) no tirofiban group (n = 36), no tirofiban injection regardless of PTA or ICS. Results: ICS was more frequently performed in the combined IV + IA tirofiban group than in the IA tirofiban group (100% vs 46%, p