Antiproliferative activities through accelerating autophagic flux by basidalin and its analogs in human cancer cells.

Basidalin, isolated from the basidiomycete Leucoagaricus naucina, has previously demonstrated antibacterial and antitumor properties against murine cancer cells in vivo, but its effects on human cancer cells remain unknown. In this study, we found that basidalin possesses antiproliferative activity against human cancer cell lines. To elucidate the antiproliferative mechanism of basidalin, we focused on autophagy. Treatment with basidalin led to an increase in LC3-II expression level, and accelerated autophagic flux through an mTOR-independent pathway. Moreover, according to the structure-activity relationship analysis-including newly synthesized basidalin analogs-the formyl group, not the amino group, contributes to the antiproliferative activities of basidalin against human cancer cells. Additionally, the antiproliferative activity of basidalin analogs was strongly correlated with autophagy-inducing activity, indicating that basidalin exhibits antiproliferative activity through autophagy induction. These data suggest that basidalin, characterized by its ability to upregulate autophagic flux, emerges as a novel anticancer drug.

Lithium treatment rescues dysfunctional autophagy in the cell models of Tay-Sachs disease.

Tay-Sachs disease is a rare lysosomal storage disorder (LSD) caused by a mutation in the HexA gene coding ß-hexosaminidase A enzyme. The disruption of the HexA gene causes the accumulation of GM2 ganglioside resulting in progressive neurodegeneration in humans. Surprisingly, Hexa-/- mice did not show neurological phenotypes. Our group recently generated a murine model of Tay-Sachs disease exhibiting excessive GM2 accumulation and severe neuropathological abnormalities mimicking Tay-Sachs patients. Previously, we reported impaired autophagic flux in the brain of Hexa/-Neu3-/- mice. However, regulation of autophagic flux using inducers has not been clarified in Tay-Sachs disease cells. Here, we evaluated the effects of lithium treatment on dysfunctional autophagic flux using LC3 and p62 in the fibroblast and neuroglia of Hexa-/-Neu3-/- mice and Tay-Sachs patients. We discovered the clearance of accumulating autophagosomes, aggregate-prone metabolites, and GM2 ganglioside under lithium-induced conditions. Our data suggest that targeting autophagic flux with an autophagy inducer might be a rational therapeutic strategy for the treatment of Tay-Sachs disease.

Unraveling the Janus-Faced Role of Autophagy in Hepatocellular Carcinoma: Implications for Therapeutic Interventions.

This review aims to provide a comprehensive understanding of the molecular mechanisms underlying autophagy and mitophagy in hepatocellular carcinoma (HCC). Autophagy is an essential cellular process in maintaining cell homeostasis. Still, its dysregulation is associated with the development of liver diseases, including HCC, which is one of leading causes of cancer-related death worldwide. We focus on elucidating the dual role of autophagy in HCC, both in tumor initiation and progression, and highlighting the complex nature involved in the disease. In addition, we present a detailed analysis of a small subset of autophagy- and mitophagy-related molecules, revealing their specific functions during tumorigenesis and the progression of HCC cells. By understanding these mechanisms, we aim to provide valuable insights into potential therapeutic strategies to manipulate autophagy effectively. The goal is to improve the therapeutic response of liver cancer cells and overcome drug resistance, providing new avenues for improved treatment options for HCC patients. Overall, this review serves as a valuable resource for researchers and clinicians interested in the complex role of autophagy in HCC and its potential as a target for innovative therapies aimed to combat this devastating disease.

Autophagy orchestrates resistance in hepatocellular carcinoma cells.

Treatment resistance is one of the major barriers for therapeutic strategies in hepatocellular carcinoma (HCC). Many studies have indicated that chemotherapy and radiotherapy induce autophagy machinery (cell protective autophagy) in HCC cells. In addition, many experiments report a remarkable crosstalk between treatment resistance and autophagy pathways. Thus, autophagy could be one of the key factors enabling tumor cells to hinder induced cell death after medical interventions. Therefore, extensive research on the molecular pathways involved in resistance induction and autophagy have been conducted to achieve the desired therapeutic response. The key molecular pathways related to the therapy resistance are TGF-ß, MAPK, NRF2, NF-κB, and non-coding RNAs. In addition, EMT, drug transports, apoptosis evasion, DNA repair, cancer stem cells, and hypoxia could have considerable impact on the hepatoma cell's response to therapies. These mechanisms protect tumor cells against various treatments and many studies have shown that each of them is connected to the molecular pathways of autophagy induction in HCC. Hence, autophagy inhibition may be an effective strategy to improve therapeutic outcome in HCC patients. In this review, we further highlight how autophagy leads to poor response during treatment through a complex molecular network and how it enhances resistance in primary liver cancer. We propose that combinational regimens of approved HCC therapeutic protocols plus autophagy inhibitors may overcome drug resistance in HCC therapy.

Magnolol induces cytotoxic autophagy in glioma by inhibiting PI3K/AKT/mTOR signaling.

Glioma is difficult-to-treat because of its infiltrative nature and the presence of the blood-brain barrier. Temozolomide is the only FDA-approved drug for its management. Therefore, finding a novel chemotherapeutic agent for glioma is of utmost importance. Magnolol, a neolignan, has been known for its apoptotic role in glioma. In this work, we have explored a novel anti-glioma mechanism of Magnolol associated with its role in autophagy modulation. We found increased expression levels of Beclin-1, Atg5-Atg12, and LC3-II and lower p62 expression in Magnolol-treated glioma cells. PI3K/AKT/mTOR pathway proteins were also downregulated in Magnolol-treated glioma cells. Next, we treated the glioma cells with Insulin, a stimulator of PI3K/AKT/mTOR signaling, to confirm that Magnolol induced autophagy by inhibiting this pathway. Insulin reversed the effect on Magnolol-mediated autophagy induction. We also established the same in in vivo glioma model where Magnolol showed an anti-glioma effect by inducing autophagy. To confirm the cytotoxic effect of Magnolol-induced autophagy, we used Chloroquine, a late-stage autophagy inhibitor. Chloroquine efficiently reversed the anti-glioma effects of Magnolol both in vitro and in vivo. Our study revealed the cytotoxic effect of Magnolol-induced autophagy in glioma, which was not previously reported. Additionally, Magnolol showed no toxicity in non-cancerous cell lines as well as rat organs. Thus, we concluded that Magnolol is an excellent candidate for developing new therapeutic strategies for glioma management.

Research progress on induced autophagy for the treatment of oral cancer / 口腔疾病防治

@#Oral cancer has a high degree of malignancy, easily recurs, readily metastasizes and poor progonsis. Autophagy is a catabolic process induced in cells under stressful conditions. In recent years, studies have found that the activation of autophagy in epithelial cells can inhibit carcinogenesis and activate pathways such as mTOR and MAPK to activate autophagy in oral cancer cells and inhibit their survival. Inducing autophagy can degrade eukaryotic initiation factor 4E protein and inhibit oral cancer metastasis. Inducing autophagy in oral cancer cells can inhibit their proliferation and promote their apoptosis. Adding autophagy inducers to the treatment can help improve its efficacy and patient survival compared with chemoradiotherapy alone. In addition, the induction of autophagy in oral cancer cells can improve the body's immune function and enhance the efficacy of oral cancer immunotherapy. This article summarizes the relationship between autophagy and oral cancer and the role of induced autophagy in the treatment of oral cancer with the combined application of chemoradiotherapy and immunotherapy. The goal is to provide new ideas for inducing autophagy during the treatment of oral cancer, improving the therapeutic effect of oral cancer and the survival rate of patients. At present, the mechanism of action of induced autophagy in the treatment of oral cancer is not clear. Future research should study its mechanism of action, improve its therapeutic effect on oral cancer and develop autophagy inducers to accurately regulate and induce autophagy during the treatment of oral cancer.

Autophagy takes it all - autophagy inducers target immune aging.

Autophagy, as the key nutrient recycling pathway, enables eukaryotic cells to adapt to surging cellular stress during aging and, thereby, delays age-associated deterioration. Autophagic flux declines with age and, in turn, decreases in autophagy contribute to the aging process itself and promote senescence. Here, we outline how autophagy regulates immune aging and discuss autophagy-inducing interventions that target senescent immune cells, which are major drivers of systemic aging. We examine how cutting-edge technologies, such as single-cell omics methods hold the promise to capture the complexity of molecular and cellular phenotypes associated with aging, driving the development of suitable putative biomarkers and clinical bioassays. Finally, we debate the urgency to initiate large-scale human clinical trials. We give special preference to small molecule probes and to dietary interventions that can extend healthy lifespan and are affordable for most of the world's population.

Autophagy Dysfunction as a Phenotypic Readout in hiPSC-Derived Neuronal Cell Models of Neurodegenerative Diseases.

Autophagy is an evolutionarily conserved catabolic pathway for the degradation of cytoplasmic constituents in eukaryotic cells. It is the primary disposal route for selective removal of undesirable cellular materials like aggregation-prone proteins and damaged organelles for maintaining cellular homeostasis, and for bulk degradation of intracellular macromolecules and recycling the breakdown products for providing energy homeostasis during starvation. These functions of autophagy are attributed to cellular survival and thus pertinent for human health; however, malfunction of this process is detrimental to the cells, particularly for post-mitotic neurons. Thus, basal autophagy is vital for maintaining neuronal homeostasis, whereas autophagy dysfunction contributes to neurodegeneration. Defective autophagy has been demonstrated in several neurodegenerative diseases wherein pharmacological induction of autophagy is beneficial in many of these disease models. Elucidating the mechanisms underlying defective autophagy is imperative for the development of therapies targeting this process. Disease-affected human neuronal cells can be established from patient-derived human induced pluripotent stem cells (hiPSCs) that provide a clinically relevant platform for studying disease mechanisms and drug discovery. Thus, modeling autophagy dysfunction as a phenotypic readout in patient-derived neurons provides a more direct platform for investigating the mechanisms underlying defective autophagy and evaluating the therapeutic efficacy of autophagy inducers. Toward this, several hiPSC-derived neuronal cell models of neurodegenerative diseases have been employed. In this review, we highlight the key methodologies pertaining to hiPSC maintenance and neuronal differentiation, and studying autophagy at an endogenous level in hiPSC-derived neuronal cells.

Pharmacological insights into autophagy modulation in autoimmune diseases.

As a cellular bulk degradation and survival mechanism, autophagy is implicated in diverse biological processes. Genome-wide association studies have revealed the link between autophagy gene polymorphisms and susceptibility of autoimmune diseases including systemic lupus erythematosus (SLE) and inflammatory bowel disease (IBD), indicating that autophagy dysregulation may be involved in the development of autoimmune diseases. A series of autophagy modulators have displayed protective effects on autoimmune disease models, highlighting the emerging role of autophagy modulators in treating autoimmune diseases. This review explores the roles of autophagy in the autoimmune diseases, with emphasis on four major autoimmune diseases [SLE, rheumatoid arthritis (RA), IBD, and experimental autoimmune encephalomyelitis (EAE)]. More importantly, the therapeutic potentials of small molecular autophagy modulators (including autophagy inducers and inhibitors) on autoimmune diseases are comprehensively analyzed.

Sestrin2 Regulates Osteoclastogenesis via the p62-TRAF6 Interaction.

The receptor activator of nuclear factor-kappa B ligand (RANKL) mediates osteoclast differentiation and functions by inducing Ca2+ oscillations, activating mitogen-activated protein kinases (MAPKs), and activating nuclear factor of activated T-cells type c1 (NFATc1) via the RANK and tumor necrosis factor (TNF) receptor-associated factor 6 (TRAF6) interaction. Reactive oxygen species (ROS) also plays an important role during osteoclastogenesis and Sestrin2, an antioxidant, maintains cellular homeostasis upon stress injury via regulation of ROS, autophagy, and inflammation. However, the role of Sestrin2 in osteoclastogenesis remains unknown. In this study, we investigated the role of Sestrin2 in the RANKL-RANK-TRAF6 signaling pathway during osteoclast differentiation. Deletion of Sestrin2 (Sesn2) increased bone mass and reduced the number of multinucleated osteoclasts on bone surfaces. RANKL-induced osteoclast differentiation and function decreased in Sesn2 knockout (KO) bone marrow-derived monocytes/macrophages (BMMs) due to inhibition of NFATc1 expression, but osteoblastogenesis was not affected. mRNA expression of RANKL-induced specific osteoclastogenic genes and MAPK protein expression were lower in Sesn2 KO BMMs than wild-type (WT) BMMs after RANKL treatment. However, the Sesn2 deletion did not affect ROS generation or intracellular Ca2+ oscillations during osteoclastogenesis. In contrast, the interaction between TRAF6 and p62 was reduced during osteoclasts differentiation in Sesn2 KO BMMs. The reduction in the TRAF6/p62 interaction and TRAP activity in osteoclastogenesis in Sesn2 KO BMMs was recovered to the WT level upon expression of Flag-Sesn2 in Sesn2 KO BMMs. These results suggest that Sestrin2 has a novel role in bone homeostasis and osteoclasts differentiation through regulation of NFATc1 and the TRAF6/p62 interaction.

Development of genistein-O-alkylamines derivatives as multifunctional agents for the treatment of Alzheimer's disease.

The multi-target-directed ligands have been regarded as the promising multifunctional agents for the treatment of Alzheimer's disease (AD). Based on our previous work, a series of genistein-O-alkylamines derivatives was developed to further explore the structure-activity-relationship. The results showed that compound 7d indicated reversible and highly selective hAChE inhibitory activity with IC50 value of 0.53 µM. Compound 7d also displayed good antioxidant activity (ORAC = 1.1 eq.), promising neuroprotective effect and selective metal chelation property. Moreover, compound 7d significantly inhibited self-induced, hAChE-induced and Cu2+-induced Aß aggregation with 39.8%, 42.1% and 74.1%, respectively, and disaggregated Cu2+-induced Aß1-42 aggregation (67.3%). In addition, compound 7d was a potential autophagy inducer and improved the levels of GPX4 protein. Furthermore, compound 7d presented good blood-brain-barrier permeability in vitro. More importantly, compound 7d did not show any acute toxicity at doses of up to 1000 mg/kg and presented good precognitive effect on scopolamine-induced memory impairment. Therefore, compound 7d was a promising multifunctional agent for the development of anti-AD drugs.

Pharmacological insights into autophagy modulation in autoimmune diseases

As a cellular bulk degradation and survival mechanism, autophagy is implicated in diverse biological processes. Genome-wide association studies have revealed the link between autophagy gene polymorphisms and susceptibility of autoimmune diseases including systemic lupus erythematosus (SLE) and inflammatory bowel disease (IBD), indicating that autophagy dysregulation may be involved in the development of autoimmune diseases. A series of autophagy modulators have displayed protective effects on autoimmune disease models, highlighting the emerging role of autophagy modulators in treating autoimmune diseases. This review explores the roles of autophagy in the autoimmune diseases, with emphasis on four major autoimmune diseases [SLE, rheumatoid arthritis (RA), IBD, and experimental autoimmune encephalomyelitis (EAE)]. More importantly, the therapeutic potentials of small molecular autophagy modulators (including autophagy inducers and inhibitors) on autoimmune diseases are comprehensively analyzed.

Effects of autophagy inducers on recombinant antibody production in insect cells.

Insect cells have recently proven to be an excellent platform for the high-level production of functional recombinant proteins. Autophagy is an important mechanism that promotes cell survival by eliminating damaged organelles and protein aggregates, and it also may influence recombinant protein production. In the present study, we compared the effects that autophagy inducers rapamycin, everolimus, and lithium chloride exert on recombinant lepidopteran insect cells that secrete an engineered antibody molecule. Compared with nontreatment, treatment with either rapamycin or everolimus prolonged cell growth to allow high cell density, improved viability in the declining phase, and then increased the yield of secreted antibodies. These positive effects appeared to be induced via autophagy since autophagosomes were clearly detected, particularly in cells treated with rapamycin or everolimus. Unlike rapamycin, another autophagy inducer, FK506, was ineffective in insect cells. The addition of an appropriate autophagy inducer may be effective in increasing the productivity of recombinant proteins in insect cells.

Pentaminomycins C-E: Cyclic Pentapeptides as Autophagy Inducers from a Mealworm Beetle Gut Bacterium.

Pentaminomycins C-E (1-3) were isolated from the culture of the Streptomyces sp. GG23 strain from the guts of the mealworm beetle, Tenebrio molitor. The structures of the pentaminomycins were determined to be cyclic pentapeptides containing a modified amino acid, N5-hydroxyarginine, based on 1D and 2D NMR and mass spectroscopic analyses. The absolute configurations of the amino acid residues were assigned using Marfey's method and bioinformatics analysis of their nonribosomal peptide biosynthetic gene cluster (BGC). Detailed analysis of the BGC enabled us to propose that the structural variations in 1-3 originate from the low specificity of the adenylation domain in the nonribosomal peptide synthetase (NRPS) module 1, and indicate that macrocyclization can be catalyzed noncanonically by penicillin binding protein (PBP)-type TE. Furthermore, pentaminomycins C and D (1 and 2) showed significant autophagy-inducing activities and were cytoprotective against oxidative stress in vitro.

Lactulose and Melibiose Inhibit α-Synuclein Aggregation and Up-Regulate Autophagy to Reduce Neuronal Vulnerability.

Parkinson's disease (PD) is a neurodegenerative disease characterized by selective dopaminergic (DAergic) neuronal degeneration in the substantia nigra (SN) and proteinaceous α-synuclein-positive Lewy bodies and Lewy neuritis. As a chemical chaperone to promote protein stability and an autophagy inducer to clear aggregate-prone proteins, a disaccharide trehalose has been reported to alleviate neurodegeneration in PD cells and mouse models. Its trehalase-indigestible analogs, lactulose and melibiose, also demonstrated potentials to reduce abnormal protein aggregation in spinocerebellar ataxia cell models. In this study, we showed the potential of lactulose and melibiose to inhibit α-synuclein aggregation using biochemical thioflavin T fluorescence, cryogenic transmission electron microscopy (cryo-TEM) and prokaryotic split Venus complementation assays. Lactulose and melibiose further reduced α-synuclein aggregation and associated oxidative stress, as well as protected cells against α-synuclein-induced neurotoxicity by up-regulating autophagy and nuclear factor, erythroid 2 like 2 (NRF2) pathway in DAergic neurons derived from SH-SY5Y cells over-expressing α-synuclein. Our findings strongly indicate the potential of lactulose and melibiose for mitigating PD neurodegeneration, offering new drug candidates for PD treatment.

Combination of an Autophagy Inducer and an Autophagy Inhibitor: A Smarter Strategy Emerging in Cancer Therapy.

Autophagy is considered a cytoprotective function in cancer therapy under certain conditions and is a drug resistance mechanism that represents a clinical obstacle to successful cancer treatment and leads to poor prognosis in cancer patients. Because certain clinical drugs and agents in development have cytoprotective autophagy effects, targeting autophagic pathways has emerged as a potential smarter strategy for cancer therapy. Multiple preclinical and clinical studies have demonstrated that autophagy inhibition augments the efficacy of anticancer agents in various cancers. Autophagy inhibitors, such as chloroquine and hydroxychloroquine, have already been clinically approved, promoting drug combination treatment by targeting autophagic pathways as a means of discovering and developing more novel and more effective cancer therapeutic approaches. We summarize current studies that focus on the antitumor efficiency of agents that induce cytoprotective autophagy combined with autophagy inhibitors. Furthermore, we discuss the challenge and development of targeting cytoprotective autophagy as a cancer therapeutic approach in clinical application. Thus, we need to facilitate the exploitation of appropriate autophagy inhibitors and coadministration delivery system to cooperate with anticancer drugs. This review aims to note optimal combination strategies by modulating autophagy for therapeutic advantage to overcome drug resistance and enhance the effect of antitumor therapies on cancer patients.

Human Induced Pluripotent Stem Cell Models of Neurodegenerative Disorders for Studying the Biomedical Implications of Autophagy.

Autophagy is an intracellular degradation process that is essential for cellular survival, tissue homeostasis, and human health. The housekeeping functions of autophagy in mediating the clearance of aggregation-prone proteins and damaged organelles are vital for post-mitotic neurons. Improper functioning of this process contributes to the pathology of myriad human diseases, including neurodegeneration. Impairment in autophagy has been reported in several neurodegenerative diseases where pharmacological induction of autophagy has therapeutic benefits in cellular and transgenic animal models. However, emerging studies suggest that the efficacy of autophagy inducers, as well as the nature of the autophagy defects, may be context-dependent, and therefore, studies in disease-relevant experimental systems may provide more insights for clinical translation to patients. With the advancements in human stem cell technology, it is now possible to establish disease-affected cellular platforms from patients for investigating disease mechanisms and identifying candidate drugs in the appropriate cell types, such as neurons that are otherwise not accessible. Towards this, patient-derived human induced pluripotent stem cells (hiPSCs) have demonstrated considerable promise in constituting a platform for effective disease modeling and drug discovery. Multiple studies have utilized hiPSC models of neurodegenerative diseases to study autophagy and evaluate the therapeutic efficacy of autophagy inducers in neuronal cells. This review provides an overview of the regulation of autophagy, generation of hiPSCs via cellular reprogramming, and neuronal differentiation. It outlines the findings in various neurodegenerative disorders where autophagy has been studied using hiPSC models.

13-Methylberberine improves endothelial dysfunction by inhibiting NLRP3 inflammasome activation via autophagy induction in human umbilical vein endothelial cells.

BACKGROUND: Atherosclerosis, the underlying cause of the majority of cardiovascular diseases, is a lipid-driven, inflammatory disease of the large arteries. Atherosclerotic cardiovascular disease (ASCVD) threatens human lives due to high morbidity and mortality. Many studies have demonstrated that atherosclerosis is accelerated via activation of the NLRP3 inflammasome. The NLRP3 inflammasome plays a critical role in the development of vascular inflammation and atherosclerosis. In atherosclerotic plaques, excessive generation of reactive oxygen species (ROS) activates the NLRP3 inflammasome. 13-Methylberberine (13-MB) is a newly synthesized compound used in traditional Chinese medicine that has outstanding antibacterial, antitumor, and antiobesity activities, especially anti-inflammatory activity. However, the role of 13-MB in atherosclerosis needs to be explored. METHODS: CCK-8 assays and flow cytometry were conducted to determine the cell viability and apoptotic profiles of human umbilical vein endothelial cells (HUVECs) treated with 13-MB. Carboxy-DCFH-DA and JC-10 assays were used to measure ROS and determine mitochondrial membrane potential. Western blot analysis was performed to investigate proteins that are associated with the NLRP3 inflammasome and autophagy. ELISA was used to detect and quantify inflammatory cytokines related to the NLRP3 inflammasome. Transfection and confocal microscopy were conducted to observe autophagy. RESULTS: Pretreatment with 13-MB markedly reduced cytotoxicity and apoptosis, as well as intracellular ROS production, in H2O2-induced HUVECs. Moreover, 13-MB showed a protective effect in maintaining mitochondrial membrane potential. 13-MB also suppressed NLRP3 inflammasome activation and promoted autophagy induction in HUVECs. CONCLUSION: 13-MB exerts cytoprotective effects in an H2O2-induced cell injury model by inhibiting NLRP3 inflammasome activation via autophagy induction in HUVECs. These anti-inflammatory and autophagy induction activities may provide valuable evidence for further investigating the potential role of 13-MB in atherosclerosis.

Autophagy and its role in gastric cancer.

Autophagy, which is tightly regulated by a series of autophagy-related genes (ATGs), is a vital intracellular homeostatic process through which defective proteins and organelles are degraded and recycled under starvation, hypoxia or other specific cellular stress conditions. For both normal cells and tumour cells, autophagy not only sustains cell survival but can also promote cell death. Autophagy-related signalling pathways include mTOR-dependent pathways, such as the AMPK/mTOR and PI3K/Akt/mTOR pathways, and non-mTOR dependent pathways, such as the P53 pathway. Additionally, autophagy plays a dual role in gastric carcinoma (GC), including a tumour-suppressor role and a tumour-promoter role. Long-term Helicobacter pylori infection can impair autophagy, which may eventually promote tumourigenesis of the gastric mucosa. Moreover, Beclin1, LC3 and P62/SQSTM1 are regarded as autophagy-related markers with GC prognostic value. Autophagy inhibitors and autophagy inducers show promise for GC treatment. This review describes research progress regarding autophagy and its significant role in gastric cancer.

Novel autophagy modulators: Design and synthesis of (+)-epogymnolactam analogues and structure-activity relationship.

(+)-Epogymnolactam (1) was discovered as a novel autophagy inducer from a culture of Gymnopus sp. in our laboratory. To determine structure-activity relationships among (+)-epogymnolactam analogues comparing with cerulenin (2), we synthesized 5 analogues including (-)-epogymnolactam (3) having each different functional group, and 3 analogues with different side-chain lengths. Five analogues, 3, 4, 5, 6, and 7 did not significantly increase the ratio of LC3-II to LC3-I as an autophagy marker in NIH3T3 cells. These results suggest that presence and stereochemistry of (2R,3S)-epoxy group and cyclic syn-form (1b) of 1 are important for the activity as autophagy inducer. Hexyl analogue (8) as well as 1 having butyl side-chain dose-dependently increased the ratio of LC3-II to LC3-I, whereas octyl analogue (9) and 2 rather decreased the ratio. Decyl analogue (10) did not give a change in the ratio. Although 8 seemed to be an excellent autophagy inducer, it dose-dependently increased SQSTM1 (p62) as in the case of 2, whereas 1 showed a slight dose-dependent decrease of p62 as an index of autophagic protein degradation. These observations suggest that 8 is an autophagy modulator with different molecular target from 1 or 2.