Antiphotoaging effects of solvent fractions isolated from Allomyrina dichotoma larvae extract.

Skin aging is affected by a variety of factors, including ultraviolet rays, oxidative stress, medications, smoking, and genetics. Among them, photo-aging accounts for about 80% of skin aging. The present study was evaluated to verify the potential of Allomyrina dichotoma larvae, which has recently been attracting attention as an edible insect, as an anti-aging substance. UVB irradiation at 100 mJ/cm2 was sufficient to induce photo-aging of fibroblasts within 24 h, which was alleviated after treatment with 70% ethanol extract of Allomyrina dichotoma larvae extract (ADLE). To obtain an extract from ADLE, which has a relatively high content of polyphenol compounds containing physiological activity, fractional solvent extraction was carried out using organic solvents such as hexane, chloroform, ethyl acetate, and butanol. Additionally, ethyl acetate and butanol fractions contributed to the inhibition of UVB-induced ROS production, cell damage, and senescence of fibroblasts. It was also confirmed that the two fractions can regulate the expression of MMP-1 and AP-1. In particular, the ethyl acetate fraction showed an excellent effect in recovering collagen decomposed by UVB. Therefore, these results suggest that ADLE has potential as a natural insect-derived biomaterial to inhibit UVB-induced photo-aging.

Mebendazole Impedes the Proliferation and Migration of Pancreatic Cancer Cells through SK1 Inhibition Dependent Pathway.

Pancreatic ductal adenocarcinoma (PDAC) has one of the highest mortality rates and requires the development of highly efficacious medications that can improve the efficiency of existing treatment methods. In particular, in PDAC, resistance to conventional chemotherapy reduces the effectiveness of anticancer drugs, decreasing the therapeutic efficiency. Sphingosine 1-phosphate (S1P), produced by sphingosine kinase (SK), plays a vital role in cancer growth, metastasis, chemotherapy, and drug resistance. Focusing on the structural characteristics of mebendazole (MBZ), we studied whether MBZ would affect metastasis, invasion, and drug resistance in cancer by lowering S1P production through inhibition of SK activity. MBZ selectively inhibited SK1 more than SK2 and regulated the levels of sphingolipids. MBZ inhibited the proliferation and migration of cancer cells in other PDAC cell lines. To determine whether the effect of MBZ on cancer cell growth and migration is S1P-mediated, S1P was treated, and the growth and migration of cancer cells were observed. It was found that MBZ inhibited S1P-induced cancer cell growth, and MBZ showed a growth inhibitory effect by regulating the JAK2/STAT3/Bcl-2 pathway. The phosphorylation of focal adhesion kinase (FAK), a transcription factor that regulates migration, was inhibited by MBZ, so it was found that the effect of MBZ regulates the migration of cancer cells through the S1P/FAK/vimentin pathway. In conclusion, our study suggests that the anthelmintic MBZ can be used as a potential therapeutic agent for treating PDAC and for structural synthesis studies of its analogs.

Novel Dimer Derivatives of PF-543 as Potential Antitumor Agents for the Treatment of Non-Small Cell Lung Cancer.

Lung cancer can be divided into non-small cell lung cancer (NSCLC) and small cell lung cancer, and the incidence and mortality rate are continuously increasing. In many cases, lung cancer cannot be completely treated with surgery, so chemotherapy is used in parallel; however, the treatment often fails due to drug resistance. Therefore, it is necessary to develop a new therapeutic agent with a new target. The expression of sphingosine kinase promotes cancer cell growth and survival and induces resistance to chemotherapeutic agents. Sphingosine-1-phosphate (S1P), produced by sphingosine kinase (SK), has been shown to regulate cancer cell death and proliferation. PF-543, currently known as an SK inhibitor, has been reported to demonstrate low anticancer activity in several cancers. Therefore, in this study, a derivative of PF-543 capable of increasing anticancer activity was synthesized and its efficacy was evaluated by using an NSCLC cell line and xenograft animal model. Based on the cytotoxic activity of the synthesized compound on lung cancer cells, the piperidine forms (Compounds 2 and 4) were observed to exhibit superior anticancer activity than the pyrrolidine forms of the head group (Compounds 1 and 3). Compounds 2 and 4 showed inhibitory effects on SK1 and SK2 activity, and S1P produced by SK was reduced by both compounds. Compounds 2 and 4 demonstrated an increase in the cytotoxicity in the NSCLC cells through increased apoptosis. As a result of using an SK1 and SK2 siRNA model to determine whether the cytotoxic effects of Compounds 2 and 4 were due to SK1 and SK2 inhibition, it was found that the cytotoxic effect of the derivative was SK1 and SK2 dependent. The metabolic stability of Compounds 2 and 4 was superior compared to PF-543, and the xenograft experiment was performed using Compound 4, which had more excellent MS. Compound 4 demonstrated the inhibition of tumor formation. The results of this experiment suggest that the bulky tail structure of PF-543 derivatives is effective for mediating anticancer activity, and the results are expected to be applied to the treatment of NSCLC.

Gryllus bimaculatus extract ameliorates high-fat diet-induced hyperglycemia and hyperlipidemia by inhibiting hepatic lipogenesis through AMPK activation.

Insect-based food is increasingly used and is a sustainable protein source provided by eco-friendly breeding respecting the animal welfare. The cricket Gryllus bimaculatus is an approved edible insect. In this paper, the effects of G. bimaculatus extracts (AE-GBE) on hepatic insulin resistance and the underlying mechanisms were investigated in high fat diet (HFD)-fed C57BL/6J mice. Mice were fed HFD for 6 weeks and some were concomitantly given AE-GBE orally (100 mg/kg/day). AE-GBE significantly improved glucose tolerance and insulin sensitivity by attenuating hepatic lipid accumulation measured by the reduced serum and hepatic lipid contents. Moreover, AE-GBE significantly downregulated the expression of hepatic lipogenesis-related genes and activated the AMPK signaling pathway. Therefore, AE-GBE might improve fatty liver and glucose metabolism disorders as well as insulin resistance by inhibiting the expression of proteins involved in hepatic fatty acid synthesis through AMPK activation. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-022-01117-9.

Synthesis of PP2A-Activating PF-543 Derivatives and Investigation of Their Inhibitory Effects on Pancreatic Cancer Cells.

Sphingosine kinase (SK) is involved in the growth of cells, including cancer cells. However, which of its two isotypes-SK1 and SK2-is more favorable for cancer growth remains unclear. Although PF-543 strongly and selectively inhibits SK1, its anticancer effect is not high, and the underlying reason remains difficult to explain. We previously determined that the tail group of PF-543 is responsible for its low metabolic stability (MS). In this study, compounds containing aromatic or aliphatic tails in the triazole group were synthesized, and changes in the SK-inhibitory effect and anticancer activity of PF-543 were assessed using pancreatic cancer cells. The compounds with aliphatic tails showed high inhibitory effects on pancreatic cancer cells but slightly lower selectivity for SK1. A compound with an introduced aliphatic tail activated protein phosphatase 2A (PP2A), showing an effect similar to that of FTY720. Molecular docking analysis revealed that the PP2A-binding form of this newly synthesized compound was different from that noted in the case of FTY720. This compound also improved the MS of PF-543. These results indicate that the tail structure of PF-543 influences MS.

Determining the Anticancer Activity of Sphingosine Kinase Inhibitors Containing Heteroatoms in Their Tail Structure.

Sphingosine kinase (SK) enzyme, a central player of sphingolipid rheostat, catalyzes the phosphorylation of sphingosine to the bioactive lipid mediator sphingosine 1 phosphate (S1P), which regulates cancer cell proliferation, migration, differentiation, and angiogenesis through its extracellular five G protein-coupled S1P receptors (S1PR1-5). Recently, several research studies on SK inhibitors have taken place in order use them for the development of novel anticancer-targeted therapy. In this study, we designed and synthesized analog derivatives of known SK1 inhibitors, namely RB005 and PF-543, by introducing heteroatoms at their tail structure, as well as investigated their anticancer activities and pharmacokinetic parameters in vitro. Compounds 1-20 of RB005 and PF-543 derivatives containing an aliphatic chain or a tail structure of benzenesulfonyl were synthesized. All compounds of set 1 (1-10) effectively reduced cell viability in both HT29 and HCT116 cells, whereas set 2 derivatives (11-20) showed poor anticancer effect. Compound 10, having the highest cytotoxic effect (48 h, HT29 IC50 = 6.223 µM, HCT116 IC50 = 8.694 µM), induced HT29 and HCT116 cell death in a concentration-dependent manner through the mitochondrial apoptotic pathway, which was demonstrated by increased annexin V-FITC level, and increased apoptotic marker cleaved caspase-3 and cleaved PARP. Compound 10 inhibited SK1 by 20%, and, thus, the S1P level decreased by 42%. Unlike the apoptosis efficacy, the SK1 inhibitory effect and selectivity of the PF-543 derivative were superior to that of the RB005 analog. As a result, compounds with an aliphatic chain tail exhibited stronger apoptotic effects. However, this ability was not proportional to the degree of SK inhibition. Compound 10 increased the protein phosphatase 2A (PP2A) activity (1.73 fold) similar to FTY720 (1.65 fold) and RB005 (1.59 fold), whereas compounds 11 and 13 had no effect on PP2A activation. Since the PP2A activity increased in compounds with an aliphatic chain tail, it can be suggested that PP2A activation has an important effect on anticancer and SK inhibitory activities.

SK1 Inhibitor RB005 Induces Apoptosis in Colorectal Cancer Cells through SK1 Inhibition Dependent and Independent Pathway.

BACKGROUND AND OBJECTIVE: Colorectal cancer (CRC) is the fourth leading cause of cancer- related death globally, with a high incidence rate in economically fast-growing countries. Sphingosine- 1-phosphate (S1P) is a bioactive lipid mediator that plays critical roles in cancer cell proliferation, migration, and angiogenesis converted by the isoforms of sphingosine kinase (SK1 and SK2). SK1 is highly expressed in colorectal cancer; its inhibitors suppress the formation of S1P and increase ceramide levels having a pro-apoptotic function. RB005 is a selective SK1 inhibitor and a structural analog of PP2A activator FTY720. The purpose of this study is to test whether RB005, an SK1 inhibitor, can be used as an anticancer agent by inhibiting the growth of colon cancer cells. METHODS: We performed MTT and colony-forming assay using colon cancer cell lines HT29 and HCT116 cells to examine the cell toxicity effect of RB005. To determine whether apoptosis of RB005 in colon cancer cell line is due to SK1 inhibition or other mechanisms due to its structural similarity with FTY720, we conducted LC/MS, siRNA knockdown, and PP2A activity experiments. RESULTS: RB005 notably inhibited CRC cell growth and proliferation compared to PF543 and ABC294640 by inducing the mitochondria-mediated intrinsic apoptotic pathway. Apoptotic cell death is caused by increased mitochondrial permeability Initiated by the activation of pro-apoptotic protein BAX, increased ceramides, and activation of PP2A. Also, RB005 treatment in HT29 cells did not change the expression level of SK1, but strikingly decreased SK1 activity and S1P levels. All these events of cell death and apoptosis were less effective when SK1 was knocked down by siRNA. CONCLUSION: This result indicates that RB005 shows the in-vitro anti-CRC effect by inhibiting SK1 activity and PP2A activation, increasing proapoptotic ceramide levels following the activation of the intrinsic apoptotic pathway.

Gryllus bimaculatus Extract Protects against Lipopolysaccharide-Derived Inflammatory Response in Human Colon Epithelial Caco-2 Cells.

Increased tight junction permeability and overproduction of proinflammatory cytokines are crucial pathophysiological mechanisms in inflammatory bowel disease (IBD). This study evaluated anti-inflammatory effects of aqueous ethanolic Gryllus bimaculatus extract (AE-GBE) against intestinal permeability on lipopolysaccharide (LPS)-treated Caco-2 cells. Treatment with AE-GBE increased cell viability and significantly reduced inflammatory mediators such as nitric oxide and LPS-induced reactive oxidative stress. LPS increased the expression levels of iNOS, Cox-2, and 4-hydroxylnonenal; however, these levels were attenuated by AE-GBE treatment. Moreover, the mRNA and protein expression levels of the inflammatory cytokines TNFα, IL-6, IL-1ß, and IFNγ were increased by LPS, but were significantly reduced by AE-GBE treatment. Intestinal epithelial permeability and the related expression of the proteins Zoula ocludence-1, occludin, and claudin-1 was increased by LPS treatment, and this effect was significantly reduced by AE-GBE treatment. The reduction in AMPK phosphorylation in LPS-treated Caco-2 cells was reversed in activation by co-treatment with AE-GBE. In conclusion, AE-GBE can protect epithelial cells from LPS-induced impaired barrier integrity by increasing tight junction proteins and preventing various inflammatory mediators. Thus, AE-GBE has the potential to improve inflammation-related diseases, including IBD, by inhibiting excessive production of inflammation-inducing mediators.

A Dansyl-Modified Sphingosine Kinase Inhibitor DPF-543 Enhanced De Novo Ceramide Generation.

Sphingosine-1-phosphate (S1P) synthesized by sphingosine kinase (SPHK) is a signaling molecule, involved in cell proliferation, growth, differentiation, and survival. Indeed, a sharp increase of S1P is linked to a pathological outcome with inflammation, cancer metastasis, or angiogenesis, etc. In this regard, SPHK/S1P axis regulation has been a specific issue in the anticancer strategy to turn accumulated sphingosine (SPN) into cytotoxic ceramides (Cers). For these purposes, there have been numerous chemicals synthesized for SPHK inhibition. In this study, we investigated the comparative efficiency of dansylated PF-543 (DPF-543) on the Cers synthesis along with PF-543. DPF-543 deserved attention in strong cytotoxicity, due to the cytotoxic Cers accumulation by ceramide synthase (CerSs). DPF-543 exhibited dual actions on Cers synthesis by enhancing serine palmitoyltransferase (SPT) activity, and by inhibiting SPHKs, which eventually induced an unusual environment with a high amount of 3-ketosphinganine and sphinganine (SPA). SPA in turn was consumed to synthesize Cers via de novo pathway. Interestingly, PF-543 increased only the SPN level, but not for SPA. In addition, DPF-543 mildly activates acid sphingomyelinase (aSMase), which contributes a partial increase in Cers. Collectively, a dansyl-modified DPF-543 relatively enhanced Cers accumulation via de novo pathway which was not observed in PF-543. Our results demonstrated that the structural modification on SPHK inhibitors is still an attractive anticancer strategy by regulating sphingolipid metabolism.

Anti-Inflammatory Activity of AF-13, an Antioxidant Compound Isolated from the Polar Fraction of Allomyrina dichotoma Larva, in Palmitate-Induced INS-1 Cells.

This study was conducted to evaluate the fractions isolated from Allomyrina dichotoma larva extract (ADLE) that exhibited anti-apoptotic and anti-inflammatory effects. A total of 13 fractions were eluted from ADLE by centrifugal chromatography (CPC), and the polar AF-13 fraction was selected, which exerted a relatively protective effect against fat-induced toxicity in INS-1 cells. AF-13 treatment of palmitate-treated INS-1 cells decreased the expression level of apoptosis-related proteins and DNA fragmentation. AF-13 also significantly inhibited the production of nitric oxide and reactive oxygen species and the triglyceride content induced by palmitate, and the effect was found to be similar to that with ADLE treatment. Palmitate upregulated the expression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) through the activation of NF-κB p65; however, this effect was significantly attenuated by AF-13 treatment. In conclusion, AF-13 is one of the major components of ADLE responsible for anti-apoptotic and anti-inflammatory activities.

Allomyrina dichotoma larva extract attenuates free fatty acid-induced lipotoxicity in pancreatic beta cells.

BACKGROUD/OBJECTIVES: Allomyrina dichotoma larva (ADL), one of the many edible insects recognized as future food resources, has a range of pharmacological activities. In a previous study, an ADL extract (ADLE) reduced the hepatic insulin resistance of high-fat diet (HFD)-induced diabetic mice. On the other hand, the associated molecular mechanisms underlying pancreatic beta-cell dysfunction remain unclear. This study examined the effects of ADLE on palmitate-induced lipotoxicity in a beta cell line of a rat origin, INS-1 cells. MATERIALS/METHODS: ADLE was administered to high-fat diet treated mice. The expression of apoptosis-related molecules was measured by Western blotting, and reactive oxidative stress generation and nitric oxide production were measured by DCH-DA fluorescence and a Griess assay, respectively. RESULTS: The administration of ADLE to HFD-induced diabetic mice reduced the hyperplasia, 4-hydroxynonenal levels, and the number of apoptotic cells while improving the insulin levels compared to the HFD group. Treatment of INS-1 cells with palmitate reduced insulin secretion, which was attenuated by the ADLE treatment. Furthermore, the ADLE treatment prevented palmitate-induced cell death in INS-1 cells and isolated islets by reducing the apoptotic signaling molecules, including cleaved caspase-3 and PARP, and the Bax/Bcl2 ratio. ADLE also reduced the levels of reactive oxygen species generation, lipid accumulation, and nitrite production in palmitate-treated INS-1 cells while increasing the ATP levels. This effect corresponded to the decreased expression of inducible nitric oxide synthase (iNOS) mRNA and protein. CONCLUSIONS: ADLE helps prevent lipotoxic beta-cell death in INS-1 cells and HFD-diabetic mice, suggesting that ADLE can be used to prevent or treat beta-cell damage in glucose intolerance during the development of diabetes.

Protective Effect of Cudrania tricuspidata Extract against High-Fat Diet Induced Nonalcoholic Fatty Liver Disease through Nrf-2/HO-1 Pathway.

Nonalcoholic fatty liver disease is the most common chronic disease affecting a wide range of the world's population and associated with obesity-induced metabolic syndrome. It is possibly emerging as a leading cause of life-threatening liver diseases for which a drug with a specific therapeutic target has not been developed yet. Previously, there have been reports on the benefits of Cudrania tricuspidata (CT) for treating obesity and diabetes via regulation of metabolic processes, such as lipogenesis, lipolysis, and inflammation. In this study, we investigated the ameliorative effect of orally administered 0.25% and 0.5% (w/w) CT mixed with high-fat diet (HFD) to C57BL/6J mice for 7 weeks. It was found that body weight, fat mass, hepatic mass, serum glucose level, and liver cholesterol levels were significantly reduced after CT treatment. In CT-treated HFD-fed mice, the mRNA expression levels of hepatic lipogenic and inflammatory cytokine-related genes were markedly reduced, whereas the expression level of epididymal lipogenic genes was increased. The mRNA expression level of beta-oxidation and Nrf-2/HO-1 genes significantly increased in CT-treated obese mice livers. We propose that CT alleviates hepatic steatosis by reducing oxidative stress and inflammation.

In vitro anticancer evaluation of micelles containing N-(4-(2-((4-methoxybenzyl)amino)ethyl)phenyl)heptanamide, an analogue of fingolimod.

Fingolimod has been evaluated for use as an anticancer agent. However, many steps are required to synthesize fingolimod because of its intricate structure. A fingolimod analogue, N-(4-(2-((4-methoxybenzyl)amino)ethyl)phenyl)heptanamide (MPH), also has anti-cancer effects and is easier to synthesize but is poorly soluble in water. To compensate for its poor water solubility, MPH-loaded polymeric micelles were prepared by thin film hydration method using various polymers and the physicochemical properties of the MPH-loaded micelles such as particle size, drug-loading (DL, %), and encapsulation efficiency (EE, %) were evaluated. A storage stability test was conducted to select the final formulation and the release profile of the MPH-loaded micelles was confirmed by in vitro release assay. MPH-loaded mPEG-b-PLA micelles were selected for further testing based on their stability and physicochemical properties; they were stable for stable for 14 days at 4 °C and 25 °C and for 7 days at 37 °C. They showed anti-cancer efficacy against both A549 and U87 cancer cells. Encapsulation of MPH in polymeric micelles did not decrease the in vitro cytotoxicity of MPH. The findings of this study lay the groundwork for future formulations that enable the effective and stable delivery of poorly water-soluble agents.

Allomyrina dichotoma larval extract attenuates intestinal barrier disruption by altering inflammatory response and tight junction proteins in lipopolysaccharide-induced Caco-2 cells.

Intestinal epithelial cells form a barrier between the intestinal lumen and host connective tissues and play an important role in maintaining intestinal nutrient homeostasis. This study investigated effects of Allomyrina dichotoma (rhinoceros beetle) larval extract (ADLE) on the intestinal barrier damage and explored mechanisms for reversing intestinal barrier dysfunction in lipopolysaccharide (LPS)-stimulated Caco-2, human intestinal epithelial cells. LPS reduced intestinal epithelial barrier function by increasing transepithelial electrical resistance, and this effect was significantly attenuated by ADLE treatment. ADLE also significantly countered the inhibition of tight junction-related protein expression in both LPS-induced Caco-2 cells and intestine from HFD-induced mice. Moreover, ADLE significantly decreased expression and production of inflammatory factors, such as iNOS, cox-2, nitric oxide, and cytokines induced by LPS stimulus. Reduction in phosphorylation of adenosine monophosphate-activated protein kinase was averted by ADLE treatment in LPS treated INS-1 cells. Finally, reactive oxygen stress level was decreased and ATP production was increased by ADLE treatment. ADLE appears to display gut health-promoting effects by reducing inflammation and inducing tight junction proteins in Caco-2 cells. Therefore, ADLE might be useful for preventing or treating intestine cell damage in inflammatory bowel disease.

Verification of the Necessity of the Tolyl Group of PF-543 for Sphingosine Kinase 1 Inhibitory Activity.

PF-543, the most potent sphingosine kinase (SK) inhibitor, does not demonstrate effective anticancer activity in some cancer cells, unlike other known SK1 inhibitors. PF-543 has a non-lipid structure with a unique toluene backbone; however, the importance of this structure remains unclear. Therefore, the purpose of this study was to investigate changes in SK inhibitory and anticancer activities and to explore the role of the tolyl group structure of PF-543 through various modifications. We transformed the methyl group of PF-543 into hydrogen, fluorine, and hydroxy. PF-543 derivatives in which the methyl group was substituted by hydrogen and fluorine (compound 5) demonstrated SK1 inhibitory and anticancer activities similar to PF-543. Moreover, we performed molecular modeling studies of PF-543 and compound 5. To assess the metabolic stability of PF-543 and compound 5, we determined their degree of degradation using the liver microsomes of four different animal species (human, dog, rat, and mouse). However, both PF-543 and compound 5 showed poor microsomal stability. Therefore, for the medical applications of PF-543, the structural modifications of its other parts may be necessary. Our results provide important information for the design of additional PF-543 analogs.

Synthesis and Biological Evaluation of BODIPY-PF-543.

Sphingosine-1-phosphate (S1P) regulates the proliferation of various cells and promotes the growth of cancer cells. Sphingosine kinase (SK), which transforms sphingosine into S1P, has two isotypes: SK1 and SK2. To date, both isotypes are known to be involved in the proliferation of cancer cells. PF-543, an SK1 inhibitor developed by Pfizer, strongly inhibits SK1. However, despite its strong SK1 inhibitory effect, PF-543 shows low anticancer activity in vitro. Therefore, additional biological evidence on the anticancer activity of SK1 inhibitor is required. The present study aimed to investigate the intracellular localization of PF-543 and identify its association with anticancer activity by introducing a fluoroprobe into PF-543. Boron-dipyrromethene (BODIPY)-introduced PF-543 has a similar SK1 inhibitory effect as PF-543. These results indicate that the introduction of BODIPY does not significantly affect the inhibitory effect of SK1. In confocal microscopy after BODIPY-PF-543 treatment, the compound was mainly located in the cytosol of the cells. This study demonstrated the possibility of introducing fluorescent material into an SK inhibitor and designing a synthesized compound that is permeable to cells while maintaining the SK inhibitory effect.

Allomyrina dichotoma Larva Extract Ameliorates the Hepatic Insulin Resistance of High-Fat Diet-Induced Diabetic Mice.

Allomyrina dichotoma larva is a nutritional-worthy future food resource and it contributes to multiple pharmacological functions. However, its antidiabetic effect and molecular mechanisms are not yet fully understood. Therefore, we investigated the hypolipidemic effect of A. dichotoma larva extract (ADLE) in a high-fat diet (HFD)-induced C57BL/6J mice model. Glucose tolerance and insulin sensitivity in HFD-induced diabetic mice significantly improved after ADLE administration for six weeks. The levels of serum triglyceride (TG), aspartate aminotransferase (AST), alanine transferase (ALT) activity, and lipid accumulation were increased in the liver of HFD-fed mice, but the levels were significantly reduced by the ADLE treatment. Moreover, hepatic fibrosis and inflammatory gene expression in the liver from HFD-treated mice were ameliorated by the ADLE treatment. Dephosphorylation of AMP-activated protein kinase (AMPK) by palmitate was inhibited in the ADLE treated HepG2 cells, and subsequently reduced expression of lipogenic genes, such as SREPBP-1c, ACC, and FAS were observed. The reduced expression of lipogenic genes and an increased phosphorylation of AMPK was also observed in the liver from diabetic mice treated with ADLE. In conclusion, ADLE ameliorates hyperlipidemia through inhibition of hepatic lipogenesis via activating the AMPK signaling pathway. These findings suggest that ADLE and its constituent bioactive compounds are valuable to prevent or treat hepatic insulin resistance in type 2 diabetes.

Synthesis and Biological Evaluation of PF-543 Derivative Containing Aliphatic Side Chain.

The PF-543 is known as a potent and selective inhibitor of sphingosine kinase (SK) 1 amongst all the SK inhibitors known to date. In a recently reported study by Pfizer on the synthesis of PF-543 derivatives and the SK inhibitory effects, the introduction of propyl moiety into sulfonyl group of PF-543 in the case of 26b revealed an excellent result of 1.7 nM of IC50 of SK1, suggesting the potential substitution of chain structure for benzenesulfonyl structure. In the present work, we aimed for identification of antitumor activity and inhibitory effects of PF-543 derivative containing aliphatic long chain (similar to known SK inhibitors) on SK1. The synthesized compound 2 exhibited an inhibitory effect on SK1 in a manner similar to that of PF-543; the PF-543 derivative manifested similar antitumor activity on HT29, HCT116 (colorectal cancer cell line), and AGS (gastric cancer cell line) cells. Also, from the docking study conducted with PF-543 and compound 2, it was apparent that the aliphatic chain in compound 2 could probably replace benzenesulfonyl structure of PF-543.

Synthesis of Novel FTY720 Analogs with Anticancer Activity through PP2A Activation.

FTY720 inhibits various cancers through PP2A activation. The structure of FTY720 is also used as a basic structure for the design of sphingosine kinase (SK) inhibitors. We have synthesized derivatives using an amide chain in FTY720 with a phenyl backbone, and then compounds were screened by an MTT cell viability assay. The PP2A activity of compound 7 was examined. The phosphorylation levels of AKT and ERK, downstream targets of PP2A, in the presence of compound 7, were determined. Compound 7 may exhibit anticancer effects through PP2A activation rather than the mechanism by inhibition of SK1 in cancer cells. In the docking study of compound 7 and PP2A, the amide chain of compound 7 showed an interaction with Asn61 that was different from FTY720, which is expected to affect the activity of the compound.

Synthesis and Biological Evaluation of FTY720 (Fingolimod) Derivatives with Aromatic Head Group as Anticancer Agents.

FTY720 is employed for the treatment of multiple sclerosis and exerts apoptotic effects on various cancers through protein phosphatase 2A (PP2A) activation. In compound 4, the dihydroxy head group of FTY720 was modified into dihydroxy phenyl group. The cell survival in compound 4 treated colorectal and gastric cancer cells was significantly reduced as compared with control, 34.6 and 25.1%, respectively. The docking study of compound 4 showed that the aromatic head group effectively binds to PP2A.