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Our recent studies have identified p21-activated kinase 4 (PAK4) as a key regulator of lipid catabolism in the liver and adipose tissue, but its role in glucose homeostasis in skeletal muscle remains to be explored. In this study, we find that PAK4 levels are highly upregulated in the skeletal muscles of diabetic humans and mice. Skeletal muscle-specific Pak4 ablation or administering the PAK4 inhibitor in diet-induced obese mice retains insulin sensitivity, accompanied by AMPK activation and GLUT4 upregulation. We demonstrate that PAK4 promotes insulin resistance by phosphorylating AMPKα2 at Ser491, thereby inhibiting AMPK activity. We additionally show that skeletal muscle-specific expression of a phospho-mimetic mutant AMPKα2 S491D impairs glucose tolerance, while the phospho-inactive mutant AMPKα2 S491A improves it. In summary, our findings suggest that targeting skeletal muscle PAK4 may offer a therapeutic avenue for type 2 diabetes., (© 2024. The Author(s).)

Parathyroid hormone (PTH) serves dual roles in bone metabolism, exhibiting both anabolic and catabolic effects. The anabolic properties of PTH have been utilized in the treatment of osteoporosis with proven efficacy in preventing fractures. Despite these benefits, PTH can be administered therapeutically for up to 2 years, and its use in patients with underlying malignancies remains a subject of ongoing debate. These considerations underscore the need for a more comprehensive understanding of the underlying mechanisms. p21-activated kinase 4 (PAK4) is involved in bone resorption and cancer-associated osteolysis; however, its role in osteoblast function and PTH action remains unknown. Therefore, in this study, we aimed to clarify the role of PAK4 in osteoblast function and its effects on PTH-induced anabolic activity. PAK4 enhanced MC3T3-E1 osteoblast viability and proliferation and upregulated cyclin D1 expression. PAK4 also augmented osteoblast differentiation, as indicated by increased mineralization found by alkaline phosphatase and Alizarin Red staining. Treatment with PTH (1-34), an active PTH fragment, stimulated PAK4 expression and phosphorylation in a protein kinase A-dependent manner. In addition, bone morphogenetic protein-2 (which is known to promote bone formation) increased phosphorylated PAK4 (p-PAK4) and PAK4 levels. PAK4 regulated the expression of both phosphorylated and total β-catenin, which are critical for osteoblast proliferation and differentiation. Moreover, p-PAK4 directly interacted with β-catenin, and disruption of β-catenin's binding to T-cell factor impaired PAK4- and PTH-induced osteoblast differentiation. Our findings elucidate the effect of PAK4 on enhancing bone formation in osteoblasts and its pivotal role in the anabolic activity of PTH mediated through its interaction with β-catenin. These insights improve the understanding of the mechanisms underlying PTH activity and should inform the development of more effective and safer osteoporosis treatments., (© 2024 Wiley Periodicals LLC.)

An aminophenol-linked naphthoquinone-based fluorometric and colorimetric chemosensor 2-chloro-3-((3-hydroxyphenyl) amino) naphthalene-1,4-dione (2CAN-Dione) was synthesized for selective detection of Sn 2+ ion in aqueous solution. The amine and conversion of carbonyl into carboxyl groups play a vital role in the sensing mechanism when Sn 2+ is added to 2CAN-Dione. Comprehensive characterization of the sensor was carried out using standard spectral and analytical approaches. Because of the intramolecular charge transfer (ICT) effect and the turn-on sensing mode, the strong fluorometric emission towards Sn 2+ was observed at about 435 nm. The chemosensor exhibited good selectivity for Sn 2+ in the presence of coexisting metal ions. An improved linear connection was established with a low limit of detection (0.167 μM). FT-IR, 1 H NMR, 13 C NMR, and quantum chemistry methods were performed to verify the binding coordination mechanism. The chemosensing probe 2CAN-Dione was successfully employed in bioimaging investigations, demonstrating that it is a reliable fluorescent marker for Sn 2+ in human cancer cells., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Scope: Cannabidiol (CBD), the most abundant non-psychoactive constituent of the plant Cannabis sativa, is known to possess immune modulatory properties. This study investigates the effects of CBD on mast cell degranulation in human and mouse primary mast cells and passive cutaneous anaphylaxis in mice., Methods and Results: Mouse bone marrow-derived mast cells and human cord-blood derived mast cells are generated. CBD suppressed antigen-stimulated mast cell degranulation in a concentration-dependent manner. Mechanistically, CBD inhibited both the phosphorylation of FcεRI downstream signaling molecules and calcium mobilization in mast cells, while exerting no effect on FcεRI expression and IgE binding to FcεRI. These suppressive effects are preserved in the mast cells that are depleted of type 1 (CB1) and type 2 (CB2) cannabinoid receptors, as well as in the presence of CB1 agonist, CB2 agonist, CB1 inverse agonist, and CB2 inverse agonist. CBD also inhibited the development of mast cells in a long-term culture. The intraperitoneal administration of CBD suppressed passive cutaneous anaphylaxis in mice as evidenced by a reduction in ear swelling and decrease in the number of degranulated mast cells., Conclusion: Based on these results, the administration of CBD is a new therapeutic intervention in mast cell-associated anaphylactic diseases., (© 2023 Wiley-VCH GmbH.)

Adipose tissue lipolysis is mediated by cAMP-protein kinase A (PKA)-dependent intracellular signalling. Here, we show that PKA targets p21-activated kinase 4 (PAK4), leading to its protein degradation. Adipose tissue-specific overexpression of PAK4 in mice attenuates lipolysis and exacerbates diet-induced obesity. Conversely, adipose tissue-specific knockout of Pak4 or the administration of a PAK4 inhibitor in mice ameliorates diet-induced obesity and insulin resistance while enhancing lipolysis. Pak4 knockout also increases energy expenditure and adipose tissue browning activity. Mechanistically, PAK4 directly phosphorylates fatty acid-binding protein 4 (FABP4) at T126 and hormone-sensitive lipase (HSL) at S565, impairing their interaction and thereby inhibiting lipolysis. Levels of PAK4 and the phosphorylation of FABP4-T126 and HSL-S565 are enhanced in the visceral fat of individuals with obesity compared to their lean counterparts. In summary, we have uncovered an important role for FABP4 phosphorylation in regulating adipose tissue lipolysis, and PAK4 inhibition may offer a therapeutic strategy for the treatment of obesity., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

Antimicrobial resistance (AMR) interferes with the effective treatment of infections and increases the risk of microbial spread and infection-related illness and death. The synergistic activities of combinations of antimicrobial compounds offer satisfactory approaches to some extent. Structurally diverse naphthoquinones (NQs) including menadione (-CH 3 group at C2) exhibit substantial antimicrobial activities against multidrug-resistant (MDR) pathogens. We explored the combinations of menadione with antibiotic ciprofloxacin or ampicillin against Staphylococcus aureus and its biofilms. We found an additive (0.590 %) were also observed. However, preformed biofilms were not affected. Dent formation was also evident in S. aureus treated with the test compounds. The structure-function relationship (SFR) of NQs was used to determine and predict their activity pattern against pathogens. Analysis of 10 structurally distinct NQs revealed that the compounds with -Cl, -Br, -CH 3 , or -OH groups displayed the lowest MICs (32-256 μg/mL). Furthermore, 1,4-NQs possessing a halogen or -CH 3 moiety showed elevated ROS activity, whereas molecules with an -OH group affected cell integrity. Improved activity of antimicrobial combinations and SFR approaches are significant in antimicrobial therapies., (© 2023 Wiley-VCH GmbH.)

PPARα corepressor NCoR1 is a key regulator of fatty acid β-oxidation and ketogenesis. However, its regulatory mechanism is largely unknown. Here, we report that oncoprotein p21-activated kinase 4 (PAK4) is an NCoR1 kinase. Specifically, PAK4 phosphorylates NCoR1 at T1619/T2124, resulting in an increase in its nuclear localization and interaction with PPARα, thereby repressing the transcriptional activity of PPARα. We observe impaired ketogenesis and increases in PAK4 protein and NCoR1 phosphorylation levels in liver tissues of high fat diet-fed mice, NAFLD patients, and hepatocellular carcinoma patients. Forced overexpression of PAK4 in mice represses ketogenesis and thereby increases hepatic fat accumulation, whereas genetic ablation or pharmacological inhibition of PAK4 exhibites an opposite phenotype. Interestingly, PAK4 protein levels are significantly suppressed by fasting, largely through either cAMP/PKA- or Sirt1-mediated ubiquitination and proteasome degradation. In this way, our findings provide evidence for a PAK4-NCoR1/PPARα signaling pathway that regulates fatty acid β-oxidation and ketogenesis., (© 2023. Springer Nature Limited.)

Background: Silent information regulator 1 (SIRT1), a type III histone deacetylase, is involved in various cutaneous and systemic autoimmune diseases including systemic lupus erythematosus, rheumatoid arthritis, and psoriasis. However, little is known about the role of SIRT1 in the development of alopecia areata (AA)., Objectives: This study investigated whether SIRT1 regulates the hair follicle immune system and is involved in AA pathogenesis., Methods: SIRT1 expression in human scalp tissue was analyzed using immunohistochemical staining, qPCR, and western blotting. The regulatory effect of SIRT1 was evaluated after stimulation with the double-stranded RNA mimic polyinosinic:polycytidylic acid (poly I:C) in hair follicle outer root sheath (ORS) cells and C3H/HeJ mice., Results: SIRT1 expression was significantly reduced in the AA scalp compared to the normal scalp. SIRT1 inhibition upregulated MHC class I polypeptide-related sequence A and UL16 binding protein 3 in hair follicle ORS cells. SIRT1 inhibition also promoted the production of Th1 cytokines (IFN-γ and TNF-α), IFN-inducible chemokines (CXCL9 and CXCL10), and T cell migration in ORS cells. Conversely, SIRT1 activation suppressed the autoreactive inflammatory responses. The counteractive effect of the immune response by SIRT1 was mediated through the deacetylation of NF-κB and phosphorylation of STAT3., Conclusion: SIRT1 downregulation induces immune-inflammatory responses in hair follicle ORS cells and may contribute to AA development., Competing Interests: Declaration of Competing Interest The authors state no conflict of interest., (Copyright © 2023 Japanese Society for Investigative Dermatology. Published by Elsevier B.V. All rights reserved.)

Purpose: In our previous study, we showed that Lycium chinense Miller fruit extract (LFE) exerted hepatoprotective effects in mice. In the current study, we examined the effect of LFE on liver enzyme levels in subjects with mild hepatic dysfunction., Methods: A total of 90 subjects, aged 19 to 70 years old, with abnormal alanine aminotransferase (ALT) levels, were randomly placed into either an LFE (n = 45) treatment group or a placebo group (n = 45). During the 12-week clinical trial, subjects in each group received either LFE or placebo capsules, and were instructed to take four tablets per day (1760 mg/day). The primary outcome of the study was the changes of ALT and γ-glutamyltransferase (GGT) levels in each subject. The safety of LFE supplementation was assessed and adverse events were recorded., Results: LFE supplementation for 12 weeks resulted in a significant reduction of ALT (P = 0.0498) and GGT (P = 0.0368) levels in comparison to the placebo. No clinically significant changes were observed in any safety parameters., Conclusion: These results suggest that LFE can be applied to subjects with mild hepatic dysfunction with no possible side effects., Trial Registration: This study was registered at the Clinical Research Information Service (CRIS) as no. KCT0003985., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany.)

Adipose tissue (AT) inflammation is strongly associated with obesity-induced insulin resistance. When subjected to metabolic stress, adipocytes become inflamed and secrete a plethora of cytokines and chemokines, which recruit circulating immune cells to AT. Although sirtuin 6 (Sirt6) is known to control genomic stabilization, aging, and cellular metabolism, it is now understood to also play a pivotal role in the regulation of AT inflammation. Sirt6 protein levels are reduced in the AT of obese humans and animals and increased by weight loss. In this review, we summarize the potential mechanism of AT inflammation caused by impaired action of Sirt6 from the immune cells' point of view. We first describe the properties and functions of immune cells in obese AT, with an emphasis on discrete macrophage subpopulations which are central to AT inflammation. We then highlight data that links Sirt6 to functional phenotypes of AT inflammation. Importantly, we discuss in detail the effects of Sirt6 deficiency in adipocytes, macrophages, and eosinophils on insulin resistance or AT browning. In our closing perspectives, we discuss emerging issues in this field that require further investigation.

Gastric cancer (GC) is one of the most lethal cancers in South Korea, and it is a cancer of concern worldwide. 5-fluorouracil (5-Fu) is commonly used as the first-line therapy for advanced GC; however, its side effects often limit the dosage range and impair patients' quality of life. Due to the limitations of current chemotherapy, new anticancer therapies are urgently needed. 3,3'-diindolylmethane (DIM) has been reported to have the ability to protect against various types of cancer. Our study aimed to elucidate the anticancer effect of DIM in GC when treated with the chemotherapeutic agent 5-Fu. In our results, combined treatment with DIM and 5-Fu resulted in higher apoptosis and lower cell proliferation than treatment with 5-Fu in SNU484 and SNU638 cell lines. Furthermore, when DIM and 5-Fu were administered together, cell invasion was diminished by mediated E-cadherin, MMP-9, and uPA; p-Akt and p-GSK-3 β levels were reduced more significantly than when 5-Fu was administered alone. Moreover, in the Wnt signaling pathway, combined treatment of DIM and 5-Fu diminished β -catenin levels in the nucleus and inhibited cyclin D1and c-Myc protein levels. The Akt inhibitor, wortmannin, further inhibited the levels of β -catenin and c-Myc that were inhibited by DIM and 5-Fu. Furthermore, an animal xenograft model demonstrated that DIM combined with 5-Fu considerably reduced tumor growth without any toxic effects by regulating the Akt/GSK-3 β and β -catenin levels. Our findings suggest that DIM significantly potentiates the anticancer effects of 5-Fu by targeting the Akt/GSK-3 β and WNT/ β -catenin because the combination therapy is more effective than 5-Fu alone, thereby offering an innovative potential therapy for patients with GC., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2023 Cong Shan Li et al.)

Prostate cancer (PCa) is the most commonly diagnosed genital cancer in men worldwide. Around 80% of the patients who developed advanced PCa suffered from bone metastasis, with a sharp drop in the survival rate. Despite great efforts, the detailed mechanisms underlying castration-resistant PCa (CRPC) remain unclear. Sirtuin 5 (SIRT5), an NAD + -dependent desuccinylase, is hypothesized to be a key regulator of various cancers. However, compared to other SIRTs, the role of SIRT5 in cancer has not been extensively studied. Here, we revealed significantly decreased SIRT5 levels in aggressive PCa cells relative to the PCa stages. The correlation between the decrease in the SIRT5 level and the patient's reduced survival rate was also confirmed. Using quantitative global succinylome analysis, we characterized a significant increase in the succinylation at lysine 118 (K118su) of lactate dehydrogenase A (LDHA), which plays a role in increasing LDH activity. As a substrate of SIRT5, LDHA-K118su significantly increased the migration and invasion of PCa cells and LDH activity in PCa patients. This study reveals the reduction of SIRT5 protein expression and LDHA-K118su as a novel mechanism involved in PCa progression, which could serve as a new target to prevent CPRC progression for PCa treatment., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Colorectal cancer (CRC) is one of the deadliest malignant tumors worldwide and its prevalence is increasing in South Korea. The efficacy of combined treatment with natural product‑derived and chemotherapy agents including curcumin combined with 5‑fluorouracil, resveratrol combined with cisplatin and epigallocatechin‑3‑gallate (EGCG) combined with cisplatin in preventing cancer progression and killing cancer cells has emerged. The Akt and Hippo signaling pathways serve a key role in colorectal tumor growth; however, the exact role of the crosstalk between Akt and Hippo signaling pathways in CRC remains poorly elucidated. The combined effect of UA and DOX on the cell proliferation, apoptosis, migration and cell cycle of CRC cells were investigated by performing Cell proliferation assay, a soft agar colony formation assay, flow cytometry, wound healing assay and western blotting assay. Subsequently, the expression of AKT and Hippo signaling pathway‑associated proteins were also assessed by western blot assay. Moreover, a xenograft nude mouse model was constructed to verify the effects of UA and DOX on the tumorigenesis of HCT116 cell in vivo . The present study reported that ursolic acid (UA) strongly enhanced the antitumor action of doxorubicin (DOX) via blocking the Akt/glycogen synthase kinase‑3β (Gsk3β) signaling pathway and activating tumor‑suppressive Hippo signaling (mammalian Ste20‑like kinase 1 and 2, salvador family WW domain containing protein 1 and MOB kinase activator 1), thereby downregulating downstream effector yes‑associated protein 1 (Yap) and connective tissue growth factor (CTGF) protein expression levels in CRC cells. Furthermore, The PI3K inhibitor LY294002 further suppressed Akt activity and enhance the function of Hippo pathway‑associated proteins in DOX + UA treated cells; this effect led to subsequent oncogenic Yap and CTGF inhibition following combined treatment, whereas Akt activator SC79 exerted an opposite effect in CTGF expression. In vivo , treatment with UA combined with DOX markedly suppressed the progression of CRC without any toxic effects on a xenograft mouse model by disrupting Akt signaling and activating the Hippo signaling pathway. These results demonstrated that UA and DOX treatment successfully induced Akt/Gsk3β inactivation via Hippo signaling pathway activation to promote Yap degradation, resulting in the inhibition of colorectal tumorigenesis. In conclusion, these findings suggested that combination therapy with UA and DOX may be more effective than DOX alone. UA may be a novel anticancer strategy and could be considered for investigation as a complementary chemotherapy agent in the future.

p21-Activated kinase 4 (PAK4), one of the serine/threonine kinases activated by Rho-family GTPases, has been widely studied as an oncogenic protein that is overexpressed in many types of cancers. In our recent study, PAK4 upregulation was observed in mice exhibiting hepatic ischaemia-reperfusion (I/R) and in liver transplantation patients. Liver I/R injury was also attenuated in Pak4 KO mice. Herein, we report a novel series of pyrazolo[3,4- d ]pyrimidine derivatives of type I ½ PAK4 inhibitors. The most potent compound SPA7012 was evaluated to determine the pharmacological potential of PAK4 inhibitor in I/R injury in mice. Mice with I/R injury showed typical patterns of liver damage, as demonstrated by increases in serum levels of aminotransferases and proinflammatory cytokines, hepatocellular necrosis and apoptosis, and inflammatory cell infiltration, relative to sham mice. Conversely, intraperitoneal administration of SPA7012 dramatically attenuated biochemical and histopathologic changes. Mechanistically, stabilisation of nuclear factor-erythroid 2-related factor 2 (Nrf2), a master regulator of anti-oxidative response, was observed following SPA7012 treatment. SPA7012 treatment in primary hepatocytes also attenuated hypoxia-reoxygenation-induced apoptotic cell death and inflammation. Together, these results provide experimental evidence supporting the use of PAK4 inhibitors for alleviation of I/R-induced liver damage.

Sirtuin 1 (SIRT1) regulates cellular processes by deacetylating non-histone targets, including transcription factors and intracellular signalling mediators; thus, its abnormal activation is closely linked to the pathophysiology of several diseases. However, its function in Toxoplasma gondii infection is unclear. We found that SIRT1 contributes to autophagy activation via the AMP-activated protein kinase (AMPK) and PI3K/AKT signalling pathways, promoting anti- Toxoplasma responses. Myeloid-specific Sirt1 -/- mice exhibited an increased cyst burden in brain tissue compared to wild-type mice following infection with the avirulent ME49 strain. Consistently, the intracellular survival of T. gondii was markedly increased in Sirt1 -deficient bone-marrow-derived macrophages (BMDMs). In contrast, the activation of SIRT1 by resveratrol resulted in not only the induction of autophagy but also a significantly increased anti- Toxoplasma effect. Notably, SIRT1 regulates the FoxO-autophagy axis in several human diseases. Importantly, the T. gondii -induced phosphorylation, acetylation, and cytosolic translocation of FoxO1 was enhanced in Sirt1 -deficient BMDMs and the pharmacological inhibition of PI3K/AKT signalling reduced the cytosolic translocation of FoxO1 in BMDMs infected with T. gondii . Further, the CaMKK2-dependent AMPK signalling pathway is responsible for the effect of SIRT1 on the FoxO3a-autophagy axis and for its anti- Toxoplasma activity. Collectively, our findings reveal a previously unappreciated role for SIRT1 in Toxoplasma infection.

The layered Ni-rich NiCoMn (NCM)-based cathode active material Li[Ni x Co (1-x)/2 Mn (1-x)/2 ]O 2 (x ≥ 0.6) has the advantages of high energy density and price competitiveness over an LiCoO 2 -based material. Additionally, NCM is beneficial in terms of its increasing reversible discharge capacity with the increase in Ni content; however, stable electrochemical performance has not been readily achieved because of the cation mixing that occurs during its synthesis. In this study, various layer-structured Li 1.0 [Ni 0.8 Co 0.1 Mn 0.1 ]O 2 materials were synthesized, and their electrochemical performances were investigated. A NiCoMnCO 3 precursor, prepared using carbonate co-precipitation with Li 2 CO 3 as the lithium source and having a sintering temperature of 850 °C, sintering time of 25 h, and metal to Li molar ratio of 1.00-1.05 were found to be the optimal parameters/conditions for the preparation of Li 1.0 [Ni 0.8 Co 0.1 Mn 0.1 ]O 2 . The material exhibited a discharge capacity of 160 mAhg -1 and capacity recovery rate of 95.56% (from a 5.0-0.1 C-rate).

Switching myofibers from the fast-glycolytic type to the slow-oxidative type is associated with an alleviation of the symptoms associated with various cardiometabolic diseases. This study investigates the effect of Vitis vinifera Jingzaojing leaf and shoot extract (JLSE), which is rich in phenolic compounds, on the regulation of skeletal muscle fiber-type switching, as well as the associated underlying mechanism. Male C57BL/6N mice were supplemented orally with vehicle or JLSE (300 mg/kg) and subjected to treadmill exercise training. After four weeks, mice in the JLSE-supplemented group showed significantly improved exercise endurance and mitochondrial oxidative capacity. JLSE supplementation increased the expression of sirtuin 6 and decreased Sox6 expression, thereby elevating the number of mitochondria and encouraging fast-to-slow myofiber switching. The results of our experiments suggest that JLSE supplementation reprograms myofiber composition to favor the slow oxidative type, ultimately enhancing exercise endurance.

The purpose of this study was to examine whether Limonium tetragonum , cultivated in a smart-farming system with LED lamps, could increase exercise capacity in mice. C57BL/6 male mice were orally administered vehicle or Limonium tetragonum water extract (LTE), either 30 or 100 mg/kg, and were subjected to moderate intensity treadmill exercise for 4 weeks. Running distance markedly increased in the LTE group (100 mg/kg) by 80 ± 4% compared to the vehicle group, which was accompanied by a higher proportion of oxidative fibers (6 ± 6% vs. 10 ± 4%). Mitochondrial DNA content and gene expressions related to mitochondrial biogenesis were significantly increased in LTE-supplemented gastrocnemius muscles. At the molecular level, the expression of PGC-1α, a master regulator of fast-to-slow fiber-type transition, was increased downstream of the PKA/CREB signaling pathway. LTE induction of the PKA/CREB signaling pathway was also observed in C2C12 cells, which was effectively suppressed by PKA inhibitors H89 and Rp-cAMP. Altogether, these findings indicate that LTE treatment enhanced endurance exercise capacity via an improvement in mitochondrial biosynthesis and the increases in the formation of oxidative slow-twitch fibers. Future study is warranted to validate the exercise-enhancing effect of LTE in the human.

Non-alcoholic steatohepatitis (NASH) is a chronic liver disease that results from multiple metabolic disorders. Considering the complexity of the pathogenesis, the identification of a factor mediating the multiple pathogenic phenotypes of NASH will be important for treatment. In this study, we found that CXXC5, a negative feedback regulator of the Wnt/β-catenin pathway, was overexpressed with suppression of Wnt/β-catenin signaling and its target genes involved in hepatic metabolism in obese-NASH patients. Cxxc5 -/- mice were found to be resistant to NASH pathogenesis with metabolic improvements. KY19334, a small molecule that activates the Wnt/β-catenin pathway via interference of the CXXC5-Dvl interaction, reversed the overall pathogenic features of NASH as Cxxc5 -/- mice. The improvement in NASH by KY19334 is attributed to its regenerative effects through restorative activation of the suppressed Wnt/β-catenin signaling. Overall, the pronounced metabolic improvements with the stimulation of liver regeneration by interfering with the CXXC5-Dvl interaction provide a therapeutic approach for NASH., (© 2022. The Author(s).)

Background and Aims: p21-activated kinase 4 (PAK4), an oncogenic protein, has emerged as a promising target for anticancer drug development. Its role in oxidative stress conditions, however, remains elusive. We investigated the effects of PAK4 signaling on hepatic ischemia/reperfusion (I/R) injury., Approach and Results: Hepatocyte- and myeloid-specific Pak4 knockout (KO) mice and their littermate controls were subjected to a partial hepatic I/R (HIR) injury. We manipulated the catalytic activity of PAK4, either through genetic engineering (gene knockout, overexpression of wild-type [WT] or dominant-negative kinase) or pharmacological inhibitor, coupled with a readout of nuclear factor erythroid 2-related factor 2 (Nrf2) activity, to test the potential function of PAK4 on HIR injury. PAK4 expression was markedly up-regulated in liver during HIR injury in mice and humans. Deletion of PAK4 in hepatocytes, but not in myeloid cells, ameliorated liver damages, as demonstrated in the decrease in hepatocellular necrosis and inflammatory responses. Conversely, the forced expression of WT PAK4 aggravated the pathological changes. PAK4 directly phosphorylated Nrf2 at T369, and it led to its nuclear export and proteasomal degradation, all of which impaired antioxidant responses in hepatocytes. Nrf2 silencing in liver abolished the protective effects of PAK4 deficiency. A PAK4 inhibitor protected mice from HIR injury., Conclusions: PAK4 phosphorylates Nrf2 and suppresses its transcriptional activity. Genetic or pharmacological suppression of PAK4 alleviates HIR injury. Thus, PAK4 inhibition may represent a promising intervention against I/R-induced liver injury., (© 2022 American Association for the Study of Liver Diseases.)

Cholestatic liver disease, or cholestasis, is a condition characterized by liver inflammation and fibrosis following a bile duct obstruction and an intrahepatic accumulation of bile acids. Inhibiting inflammation is a promising therapeutic strategy for cholestatic liver diseases. Acer tegmentosum Maxim extract (ATE) is best known for its anti-inflammatory and antioxidative properties. In this study, we investigated the effects of ATE on liver injury and fibrosis in mice with bile duct ligation (BDL)-induced cholestasis through analysis of gene expression, cytokines, and histological examination. Oral administration of ATE (20 or 50 mg/kg) for 14 days significantly attenuated hepatocellular necrosis compared to vehicle-treated BDL mice, which was accompanied by the reduced level of serum bile acids and bilirubin. We determined that ATE treatment reduced liver inflammation, oxidative stress, and fibrosis. These beneficial effects of ATE were concurrent with the decreased expression of genes involved in the NF- κ B pathway, suggesting that the anti-inflammatory effect of ATE could be a possible mechanism against cholestasis-associated liver injury. Our findings substantiate ATE's role as an alternative therapeutic agent for cholestasis-induced liver injury and fibrosis.

Renal fibrosis is a significant pathologic change associated with progressive kidney disease. Sirt6 is an NAD + -dependent deacetylase and mono-ADP ribosyltransferase known to play diverse roles in the processes attendant to aging, metabolism, and carcinogenesis. However, the role of proximal tubule-specific Sirt6 in renal fibrosis remains elusive. This study investigates the effect of proximal tubule-specific Sirt6 knockdown on unilateral ureteral obstruction (UUO)-induced renal tubulointerstitial inflammation and fibrosis. Renal fibrosis in wild type and PT -Sirt6KO ( Sirt6 flox/flox ; Ggt1-Cre + ) mice was induced by UUO surgery. After seven days, histologic examination and Western blot analysis were performed to examine extracellular matrix (ECM) protein expression. We evaluated inflammatory cytokine and cell adhesion molecule expression after ureteral obstruction. The therapeutic effect of Sirt6 activator MDL-800 on UUO-induced tubulointerstitial inflammation and fibrosis was assessed. The loss of Sirt6 in the proximal tubules aggravated UUO-induced tubular injury, ECM deposition, F4/80 positive macrophage infiltration, and proinflammatory cytokine and chemokine expression. Sirt6 activator MDL-800 mitigated UUO-induced renal tubulointerstitial inflammation and fibrosis. In an in vitro experiment, MDL-800 decreases the transforming growth factor (TGF)-β1-induced activation of myofibroblast and ECM production by regulating Sirt6-dependent β-catenin acetylation and the TGF-β1/Smad signaling pathway. In conclusion, proximal tubule Sirt6 may play an essential role in UUO-induced tubulointerstitial inflammation and fibrosis by regulating Sirt6-dependent β-catenin acetylation and ECM protein promoter transcription.

Nicotinamide adenine dinucleotide (NAD + ) acts as a cofactor for multiple biological processes. While previous research has revealed that the NAD + declines associated with aging contributes to an impairment of immune cells, its role in mast cell function, especially in response to an anaphylactic condition, has remained unexplored. We tested whether the restoration of cellular NAD + concentration by the supplementation of NAD + boosting molecules prevented mast cell degranulation and anaphylactic responses. Methods: Bone marrow derived mast cells (BMMCs) and human cord blood derived mast cells were treated with NAD + precursors nicotinamide mononucleotide (NMN) and nicotinamide riboside (NR), and FcεRI downstream signaling was assessed. Animal models of passive systemic anaphylaxis (PSA) and passive cutaneous anaphylaxis (PCA) were used to investigate the effects of NAD + precursors in the anaphylactic responses of mice. Results: Treatment of murine BMMCs and human cord blood derived mast cells with NAD + precursors repressed intracellular signaling downstream of FcεRI, as well as the release of inflammatory cytokines and lipid mediators. The intraperitoneal administration of NMN or NR also markedly attenuated IgE-mediated anaphylactic responses in mouse models of PSA and PCA. These beneficial effects of NAD + precursors, however, were attenuated in mast cell-specific Sirt6 knockout mice, indicating a Sirt6 dependency for their action. Conclusion: NAD + precursors may serve as an effective therapeutic strategy that limits mast cell-mediated anaphylactic responses., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

Expanding the exercise capacity of skeletal muscle is an emerging strategy to combat obesity-related metabolic diseases and this can be achieved by shifting skeletal muscle fibers toward slow-twitch oxidative type. Here, we report that Sirt6, an anti-aging histone deacetylase, is critical in regulating myofiber configuration toward oxidative type and that Sirt6 activator can be an exercise mimetic. Genetic inactivation of Sirt6 in skeletal muscle reduced while its transgenic overexpression increased mitochondrial oxidative capacity and exercise performance in mice. Mechanistically, we show that Sirt6 downregulated Sox6, a key repressor of slow fiber specific gene, by increasing the transcription of CREB. Sirt6 expression is elevated in chronically exercised humans, and mice treated with an activator of Sirt6 showed an increase in exercise endurance as compared to exercise-trained controls. Thus, the current study identifies Sirt6 as a molecular target for reprogramming myofiber composition toward the oxidative type and for improving muscle performance., (© 2022. The Author(s).)

Although multiple studies have shown that Angelica keiskei of the Umbelliferae family has potent anti-inflammatory and antioxidative activities and that it reduces the serum bile acids in humans, whether A. keiskei has protective effects against cholestasis-induced liver injury remains unexplored until now. This study tests the hypothesis that Angelica keiskei root extract (AKE) alleviates liver injury, inflammation, and fibrosis in mouse models of acute cholestasis induced by bile duct ligation (BDL). Oral administration of AKE (200 or 500 mg/kg) attenuated hepatocellular necrosis and significantly reduced serum levels of bile acids and bilirubin in BDL mice. The critical enzyme of bile acid synthesis, CYP7A1, was repressed by AKE, suggesting that reduced bile acid production may contribute to liver protection. Moreover, we determined through gene expression and cytokine analysis and histological examination that AKE treatment decreased liver inflammation, oxidative stress, and fibrosis. AKE also suppressed the NF- κ B pathway, suggesting this as a possible mediator of its anti-inflammatory effect. Our findings substantiate that AKE may be promising for treating cholestatic liver diseases in the future.

Background/aim: Prostate cancer (PCa) is the most commonly diagnosed genital cancer in men globally. Among patients who develop advanced PCa, 80% are affected by bone metastasis, with a sharp drop in survival rate. Despite efforts, the details of mechanisms of metastasis of PCa remain unclear. SIRT5, an NAD + -dependent deacylase, is hypothesized to be a crucial regulator of various cancers. The role of SIRT5 in cancer has not been extensively studied compared to other SIRTs. In this study, we showed significantly decreased levels of SIRT5 in PC-3M, a highly aggressive PC-3 cell variant., Materials and Methods: We characterized the differentially expressed proteins between parental and SIRT5 KO PC-3 cells using quantitative proteomics analysis., Results: A significant increase in expression of interleukin-1β (IL-1β) in SIRT5 KO cells was observed, and the PI3K/AKT/NF-ĸB signaling pathway was found significantly elevated in SIRT5 KO cells by the Gene Ontology annotation and KEGG pathway functional enrichment analysis. Moreover, we confirmed that SIRT5 can bind PI3K by immunoprecipitation analysis., Conclusion: This study is the first to demonstrate a relationship between SIRT5 and PCa metastasis, suggesting that SIRT5-mediated inhibition of the PI3K/AKT/NK-kB pathway is reduced for secondary metastasis from bone to other tissues., (Copyright © 2022, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Background: Binding IgE to a cognate allergen causes aggregation of Fcε receptor I (FcεRI) in mast cells, resulting in activation of receptor-associated Src family tyrosine kinases, including Lyn and Syk. Protein tyrosine phosphatase, receptor type C (PTPRC), also known as CD45, has emerged as a positive regulator of FcεRI signaling by dephosphorylation of the inhibitory tyrosine of Lyn., Objective: Sirtuin 6 (Sirt6), a NAD + -dependent deacetylase, exhibits an anti-inflammatory property. It remains to be determined, however, whether Sirt6 attenuates mast cell-associated diseases, including anaphylaxis., Methods: FcεRI signaling and mast cell degranulation were measured after IgE cross-linking in murine bone marrow-derived mast cells (BMMCs) and human cord blood-derived mast cells. To investigate the function of Sirt6 in mast cell activation in vivo, we used mast cell-dependent animal models of passive systemic anaphylaxis (PSA) and passive cutaneous anaphylaxis (PCA)., Results: Sirt6-deficient BMMCs augmented IgE-FcεRI-mediated signaling and degranulation compared to wild-type BMMCs. Reconstitution of mast cell-deficient Kit W-sh/W-sh mice with BMMCs received from Sirt6 knockout mice developed more severe PSA and PCA compared to mice engrafted with wild-type BMMCs. Similarly, genetic overexpression or pharmacologic activation of Sirt6 suppressed mast cell degranulation and blunted responses to PCA. Mechanistically, Sirt6 deficiency increased PTPRC transcription via acetylating histone H3, leading to enhanced aggregation of FcεRI in BMMCs. Finally, we recapitulated the Sirt6 regulation of PTPRC and FcεRI signaling in human mast cells., Conclusions: Sirt6 acts as a negative regulator of FcεRI signaling cascade in mast cells by suppressing PTPRC transcription. Activation of Sirt6 may therefore represent a promising and novel therapeutic strategy for anaphylaxis., (Copyright © 2021 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)

Background and Purpose: The anthelmintic drug praziquantel has been used as a standard treatment for schistosomiasis for over 40 years. This study aimed to repurpose praziquantel to treat psoriasis., Experimental Approach: Psoriasis-like skin inflammation was induced in mice (C57 and Balb/C) by topical application of imiquimod or intradermal injection of recombinant IL-23. Praziquantel was either orally or topically administered during the psoriasis induction period., Key Results: Mice treated with either oral or topical praziquantel exhibited markedly improved psoriasiform skin symptoms when compared with control mice, as judged by disease severity score, epidermal thickening, inflammatory cell infiltration and spleen size. Flow cytometric analysis of infiltrating immune cells from mouse skin displayed reduced infiltration of Th17 cells. In vitro experiments revealed that praziquantel inhibited STAT3 phosphorylation and RORγt expression in splenic CD4 + T-cells. Praziquantel also decreased STAT3 phosphorylation in HEK-A/F cells. Down-regulation of STAT3 phosphorylation in these cells accounts for the decreased number of Th17 cells and keratinocytes., Conclusion and Implications: These results provide the first preclinical evidence that praziquantel may effectively treat psoriasis, and suggest that praziquantel alleviates symptoms in mice by inhibiting STAT3 phosphorylation, thereby suppressing Th17 immune responses., (© 2021 The British Pharmacological Society.)

Background: Skeletal muscle regeneration is an adaptive response to injury that is crucial to the maintenance of muscle mass and function. A p21-activated kinase 4 (PAK4) serine/threonine kinase is critical to the regulation of cytoskeletal changes, cell proliferation, and growth. However, PAK4's role in myoblast differentiation and regenerative myogenesis remains to be determined., Methods: We used a mouse model of myotoxin (notexin)-induced muscle regeneration. In vitro myogenesis was performed in the C2C12 myoblast cell line, primary myoblasts, and primary satellite cells. In vivo overexpression of PAK4 or kinase-inactive mutant PAK4 S474A was conducted in skeletal muscle to examine PAK4's kinase-dependent effect on muscle regeneration. The regeneration process was evaluated by determining the number and size of multinucleated myofibres and expression patterns of myogenin and eMyHC. To explore whether PAK4 inhibition improves muscle regeneration, mice were injected intramuscularly with siRNA that targeted PAK4 or orally administered with a chemical inhibitor of PAK4., Results: p21-activated kinase 4 was highly expressed during the myoblast stage, but expression gradually and substantially decreased as myoblasts differentiated into myotubes. PAK4 overexpression, but not kinase-inactive mutant PAK4 S474A overexpression, significantly impeded myoblast fusion and MyHC-positive myotube formation in C2C12 cells, primary myoblasts, and satellite cells (P < 0.01). Conversely, PAK4 silencing led to an 8.7% and a 20.3% increase in the number of multinucleated larger myotubes in C2C12 cells and primary myoblasts. Further, in vivo overexpression of PAK4 by adenovirus injection to mice prior to and after myotoxin-induced injury led to a 52.6% decrease in the number of eMyHC-positive myofibres on Day 5 in tibialis anterior muscles as compared with those injected with control adenoviruses (P < 0.01), while Ad-PAK4 S474A showed comparable muscle regeneration parameters. PAK4-induced repression of muscle regeneration coincided with an increase in phosphatase and tensin homologue (PTEN) expression and a decrease in phosphoinositide 3-kinase-Akt signalling. In contrast, PAK4 silencing reduced PTEN expression in mice. Consistent with these findings, prodrug of PAK4 inhibitor CZh-226 (30 mg/kg) orally administered to mice repressed PTEN expression and accelerated myotube formation. Subsequent mechanistic studies revealed that PAK4 directly phosphorylates PPARγ at S273 to increase its transcription activity, thereby up-regulating PTEN expression. Importantly, an analysis of the Genotype-Tissue Expression database showed a positive correlation between PAK4 and PTEN in human skeletal muscle tissues (P < 0.01)., Conclusions: p1-activated kinase 4 is a new member of PPARγ kinase, and PAK4 inhibition may have a therapeutic role as an accelerant of muscle regeneration., (© 2021 The Authors. Journal of Cachexia, Sarcopenia and Muscle published by John Wiley & Sons Ltd on behalf of Society on Sarcopenia, Cachexia and Wasting Disorders.)

Ursolic acid (UA), a pentacyclic triterpenoid extracted from various plants, inhibits cell growth, metastasis, and tumorigenesis in various cancers. Chemotherapy resistance and the side effects of paclitaxel (PTX), a traditional chemotherapy reagent, have limited the curative effect of PTX in esophageal cancer. In this study, we investigate whether UA promotes the anti-tumor effect of PTX and explore the underlying mechanism of their combined effect in esophageal squamous cell carcinoma (ESCC). Combination treatment with UA and PTX inhibited cell proliferation and cell growth more effectively than either treatment alone by inducing more significant apoptosis, as indicated by increased sub-G1 phase distribution and protein levels of cleaved-PARP and cleaved caspase-9. Similar to the cell growth suppressive effect, the combination of UA and PTX significantly inhibited cell migration by targeting uPA, MMP-9, and E-cadherin in ESCC cells. In addition, combination treatment with UA and PTX significantly activated p-GSK-3β and suppressed the activation of Akt and FOXM1 in ESCC cells. Those effects were enhanced by the Akt inhibitor LY2940002 and inverted by the Akt agonist SC79. In an in vivo evaluation of a murine xenograft model of esophageal cancer, combination treatment with UA and PTX suppressed tumor growth significantly better than UA or PTX treatment alone. Thus, UA effectively potentiates the anti-tumor efficacy of PTX by targeting the Akt/FOXM1 cascade since combination treatment shows significantly more anti-tumor potential than PTX alone both in vitro and in vivo. Combination treatment with UA and PTX could be a new strategy for curing esophageal cancer patients.

The goal of the present work was to fabricate a new low-cost, easy-to-prepare, dual-channel fluorescence chemosensor comprised of acridine-diphenylacetyl moieties (NDA) to enable remarkable Sn 4+ detection in water and biological medium. The resulting NDA-Sn 4+ complex was utilized for the distinguished identification of Cr 2 O 7 2- ions from other anions and biomolecules. These investigations involve the absorption, fluorescence, and electrochemical methods for the detection of Sn 4+ and Cr 2 O 7 2- ions in pure water. The mechanism for NDA-mediated Sn 4+ detection was experimentally determined by FT-IR, NMR titrations, mass (ESI) analyses, and DFT calculations. The obtained results indicate that the NDA chemosensor possessed excellent performance characteristics including good water solubility and compatibility, quick response time (less than 10 s), high sensitivity (Sn 4+ = 0.268 μM and Cr 2 O 7 2- = 0.160 μM), and selectivity against coexisting metals, anions, amino acids, and peptides. The chemosensor NDA induced negligible toxicity in live cells and was successfully utilized as a biomarker for the tracking of Sn 4+ in human normal and cancer cells. More importantly, NDA demonstrates distinguished recognition of Sn 4+ in human cancer cells rather than in normal live cells. Additionally, NDA was shown to act as a mitochondria-targeted probe in FaDu cells., (Copyright © 2021 Elsevier B.V. All rights reserved.)

A sea urchin-shaped, single-layer, and hollow NiO-NiS photocatalyst with a large surface area was designed for carbon dioxide (CO 2 ) conversion in this study. A d-glucose polymeric hollow frame was fabricated using a d-glucose monomer, and NiO particles were stably grown on it using the hydrothermal method to form a hollow NiO surface. The d-glucose frame was removed by heat treatment to create hollowed NiO; hollowed NiO-NiS (h-NiO-NiS) was subsequently obtained through ion exchange between the O ions in NiO and S ions in the sulfur powder. Additionally, we attempted to determine the correlation among the surface area of the h-NiO-NiS catalyst, CO 2 gas adsorption capacity, and catalyst performance. The surface area of the h-NiO-NiS catalyst was ten times larger than that of the nanometer-sized NiO-NiS (n-NiO-NiS, 21.2 m 2  g -1 ) catalyst. The CO 2 photocatalytic conversion performance of the hollowed catalyst was approximately seven times larger than that of the nanosized catalyst. As the amount of ion-exchanged S increased, methane selectivity increased, and optimal methane production was obtained when the weight ratio of NiO and sulfur powder was 1 : 4. Using temperature-programmed desorption (TPD) analyses of CO 2 and H 2 O, the adsorption of water molecules on the Ni-S surface and that of CO 2 gas on the Ni-O surface during CO 2 conversion reaction were confirmed. The h-NiO-NiS catalyst facilitated an effective charge separation through a well-developed interfacial transition between the linked NiS and NiO, and resulted in increased CO 2 photoreduction performance under sunlight., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Intermittent fasting (IF) is gaining popularity for its effectiveness in improving overall health, including its effectiveness in achieving weight loss and euglycemia. The molecular mechanisms of IF, however, are not well understood. This study investigated the relationship between adipocyte sirtuin 6 (Sirt6) and the metabolic benefits of IF. Adipocyte-specific Sirt6-knockout (aS6KO) mice and wild-type littermates were fed a high-fat diet (HFD) ad libitum for four weeks and then subjected to 12 weeks on a 2:1 IF regimen consisting of two days of feeding followed by one day of fasting. Compared with wild-type mice, aS6KO mice subjected to HFD + IF exhibited a diminished response, as reflected by their glucose and insulin intolerance, reduced energy expenditure and adipose tissue browning, and increased inflammation of white adipose tissue. Sirt6 deficiency in hepatocytes or in myeloid cells did not impair adaptation to IF. Finally, the results indicated that the impaired adipose tissue browning and reduced expression of UCP1 in aS6KO mice were accompanied by downregulation of p38 MAPK/ATF2 signaling. Our findings indicate that Sirt6 in adipocytes is critical to obtaining the improved glucose metabolism and metabolic profiles conferred by IF and that maintaining high levels of Sirt6 in adipocytes may mimic the health benefits of IF., (© 2021. The Author(s).)

A new colorimetric and ratiometric fluorescence chemosensor 4-((3-(octadecylthio)-1,4-dioxo-1,4-dihydronaphthalen-2-yl)amino)benzenesulfonamide (4DBS) was synthesized and investigated for the selective detection of Hg 2+ in DMSO-H 2 O (9:1, v/v) solution. The chemosensor was efficiently synthesized in two steps via Michael-like addition and nucleophilic substitution reactions. The ratiometric fluorescence turn-on response was obtained towards Hg 2+ , and its fluorescence emission peak was red-shifted by 140 nm with an associated color change from light maroon to pale yellow due to the intramolecular charge transfer effect. The formed coordination metal complex was further evaluated by FT-IR, 1 H NMR, and quantum chemical analyses to confirm the binding mechanism. The detection process was sensitive/reversible, and the calculated limit of detection for Hg 2+ was 0.451 µM. Furthermore, 4DBS was effectively utilized as a bioimaging agent for detection of Hg 2+ in live cells and zebrafish larvae. Additionally, 4DBS showed distinguishing detection of Hg 2+ in cancer cells in comparison with normal cells. Thus, 4DBS could be employed as an efficient bioimaging probe for discriminative identification of human cancer cells., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Several fluorescence and colorimetric chemosensory for Sn 2+ detection in an aqueous media have been reported, but applications remain limited for discriminative Sn 2+ detection in live human cells and zebrafish larvae. Herein, a mitochondria-targeted Sn 2+ "turn-on" colorimetric and fluorescence chemosensor, 2CTA, with an aggregation-induced emission (AIE) response was developed. The sensing of Sn 2+ was enabled by a reduction-enabled binding pathway, with the conversion of -C˭O groups to -C-OH groups at the naphthoquinone moiety. The color changed from light maroon to milky white in a buffered aqueous solution. The chemosensor 2CTA possessed the excellent characteristics of good water solubility, fast response (less than 10 s), and high sensitivity (79 nM) and selectivity for Sn 2+ over other metal ions, amino acids, and peptides. The proposed binding mechanism was experimentally verified by means of FT-IR and NMR studies. The chemosensor 2CTA was successfully employed to recognize Sn 2+ in live human cells and in zebrafish larvae. In addition, a colocalization study proved that the chemosensor had the ability to target mitochondria and overlapped almost completely with MitoTracker Red. Furthermore, a bioimaging study of live cells demonstrated the discriminative detection of Sn 2+ in human cancer cells and the practical applications of 2CTA in biological systems., (Copyright © 2021 Elsevier B.V. All rights reserved.)

A recent animal study demonstrated that administration of Lactobacillus plantarum HAC01 isolated from Korean kimchi improved glycemic control in type 2 diabetic mice. In the present study, we evaluated Lactobacillus plantarum HAC01's effects on metabolic parameters of prediabetic human subjects. Forty subjects with isolated impaired glucose tolerance were randomly assigned to receive a daily placebo ( n = 20) or a dose of Lactobacillus plantarum HAC01 ( n = 20) over eight weeks. The primary endpoint was a change in 2 h postprandial glucose (2h-PPG) levels and the secondary endpoints were assessment of other glucose metabolism parameters, including HbA1c, gut microbiota composition, and fecal short-chain fatty acids (SCFAs). The group with a diet supplemented with Lactobacillus plantarum HAC01 saw a significant reduction in 2h-PPG and HbA1c levels compared to the placebo group. Fasting plasma glucose, insulin, HOMA-IR, QUICKI, microbiota composition, and fecal SCFAs, however, were not significantly altered. No serious adverse effects were reported. This is the first clinical trial to show a beneficial effect of single-strain probiotic supplementation administered over eight weeks on HbA1c levels in prediabetic subjects.

There is evidence emerging that exposure to cold temperatures enhances alternative activation of macrophages in white adipose tissue (WAT), which promotes adipocyte beiging and adaptive thermogenesis. Although we recently reported that NAD + -dependent deacetylase sirtuin 6 (Sirt6) drives alternatively activated (M2) macrophage polarization, the role of myeloid Sirt6 in adaptive thermogenesis had remained elusive. In this study, we demonstrate that myeloid Sirt6 deficiency impaired both thermogenic responses and M2 macrophage infiltration in subcutaneous WAT (scWAT) during cold exposure. Moreover, the infiltration of Siglec-F-positive eosinophils in scWAT and Th2 cytokines levels was reduced in myeloid Sirt6 knockout mice. An ex vivo bone marrow-derived cell culture experiment indicated that Sirt6 was required for eosinophil differentiation independent of its deacetylase activity. Data from our in vitro experiments show that Sirt6 acted as a transcriptional cofactor of GATA-1, independent of its catalytic function as a deacetylase or ADP-ribosyltransferase. Specifically, Sirt6 physically interacted with GATA-1, and enhanced GATA-1's acetylation and transcriptional activity by facilitating its cooperation with p300. Overall, our results suggest that myeloid Sirt6 plays an important role in eosinophil differentiation and fat beiging/adaptive thermogenesis, which is at least in part due to its ability to bind GATA-1 and stimulate its transcriptional activity., (© 2021 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.)

Gastric cancer is the fifth most common cancer and the third leading cause of cancer-related deaths worldwide. Histone deacetylase (HDAC) inhibitors are a new class of cytostatic agents available for the treatment of various cancers and diseases. Although numerous clinical and pre-clinical trials on the anticancer effects of panobinostat have been conducted, only a few reports have investigated its efficacy in gastric cancer. The present study aimed to investigate the effects of panobinostat in gastric cancer cells. Panobinostat significantly inhibited the cell viability and proliferation of the gastric cancer cell lines SNU484 and SNU638 in a dose-dependent manner; it reduced the colony-forming ability of these cells. Moreover, it induced apoptosis as indicated by increased protein levels of cleaved poly ADP-ribose polymerase and cleaved caspase-3. Panobinostat induced the G2/M cell cycle arrest in SNU484 and SNU638 cells and subsequently decreased the G2/M phase regulatory-associated protein expression of p-Wee1, Myt1, and Cdc2. Furthermore, panobinostat significantly inhibited the metastasis of SNU484 and SNU638 cells by regulating the expression of MMP-9 and E-cadherin. Further, it decreased the protein levels of p-Akt and forkhead box protein M1 (FOXM1). These effects were reversed by the Akt agonist SC79 and were accelerated by the Akt inhibitor LY2940002. Moreover, tumor growth in xenograft animal experiments was suppressed by panobinostat. These results indicated that panobinostat inhibits the proliferation, metastasis, and cell cycle progression of gastric cancer cells by promoting apoptosis and inactivating Akt/FOXM1 signaling. Cumulatively, our present study suggests that panobinostat is a potential drug for the treatment of gastric cancer.

Excessive alcohol consumption is one of the most significant causes of morbidity and mortality worldwide. Alcohol is oxidized to toxic and carcinogenic acetaldehyde by alcohol dehydrogenase (ADH) and further oxidized to a non-toxic acetate by aldehyde dehydrogenase (ALDH). There are two major ALDH isoforms, cytosolic and mitochondrial, encoded by ALDH1 and ALDH2 genes, respectively. The ALDH2 polymorphism is associated with flushing response to alcohol use. Emerging evidence shows that Lactobacillus and Bifidobacterium species encode alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH) mediate alcohol and acetaldehyde metabolism, respectively. A randomized, double-blind, placebo-controlled crossover clinical trial was designed to study the effects of Lactobacillus and Bifidobacterium probiotic mixture in humans and assessed their effects on alcohol and acetaldehyde metabolism. Here, twenty-seven wild types ( ALDH2*1/*1 ) and the same number of heterozygotes ( ALDH2*2/*1 ) were recruited for the study. The enrolled participants were randomly divided into either the probiotic (Duolac ProAP4) or the placebo group. Each group received a probiotic or placebo capsule for 15 days with subsequent crossover. Primary outcomes were measurement of alcohol and acetaldehyde in the blood after the alcohol intake. Blood levels of alcohol and acetaldehyde were significantly downregulated by probiotic supplementation in subjects with ALDH2*2/*1 genotype, but not in those with ALDH2*1/*1 genotype. However, there were no marked improvements in hangover score parameters between test and placebo groups. No clinically significant changes were observed in safety parameters. These results suggest that Duolac ProAP4 has a potential to downregulate the alcohol and acetaldehyde concentrations, and their effects depend on the presence or absence of polymorphism on the ALDH2 gene.

2'-Hydroxycinnamaldehyde (HCA), the active component isolated from the stem bark of Cinnamomum cassia, exerts anticancer effects through multiple mechanisms. We recently determined that HCA inhibits signal transducer and activator of transcription 3 (STAT3) signaling in prostate cancer cells. Because STAT3 overactivation has been closely associated with the development of psoriasis, a chronic autoimmune skin disease, we examined whether HCA ameliorates skin lesions in an imiquimod-induced psoriasis-like mouse model. The results showed that intraperitoneal administration of HCA alleviated imiquimod-induced psoriasis-like dermatitis, epidermal thickening, dermal infiltration of inflammatory cells, and proinflammatory cytokine production. Mechanistically, HCA inhibited pyruvate kinase isozyme M2 and STAT3 signaling, leading to the suppression of T cell activation, Th17 cell differentiation, and keratinocyte hyperproliferation. These results suggest that HCA may be a new treatment for psoriasis and other STAT3-mediated skin disorders, such as infection, inflammation and carcinogenesis.

Bruton's agammaglobulinemia tyrosine kinase (BTK) is an important cytoplasmic tyrosine kinase involved in B‑lymphocyte development, differentiation, and signaling. Activated protein kinase C (PKC), in turn, induces the activation of mitogen‑activated protein kinase (MAPK) signaling, which promotes cell proliferation, viability, apoptosis, and metastasis. This effect is associated with nuclear factor‑κB (NF‑κB) activation, suggesting an anti‑metastatic effect of BTK inhibitors on MCF‑7 cells that leads to the downregulation of matrix metalloproteinase (MMP)‑9 expression. However, the effect of BTK on breast cancer metastasis is unknown. In this study, the anti‑metastatic activity of BTK inhibitors was examined in MCF‑7 cells focusing on MMP‑9 expression in 12‑ O ‑tetradecanoylphorbol‑13‑acetate (TPA)‑stimulated MCF‑7 cells. The expression and activity of MMP‑9 in MCF‑7 cells were investigated using quantitative polymerase chain reaction analysis, western blotting, and zymography. Cell invasion and migration were investigated using the Matrigel invasion and cell migration assays. BTK inhibitors [ibrutinib (10 µM), CNX‑774 (10 µM)] significantly attenuated TPA‑induced cell invasion and migration in MCF‑7 cells and inhibited the activation of the phospholipase Cγ2/PKCβ signaling pathways. In addition, small interfering RNA specific for BTK suppressed MMP‑9 expression and cell metastasis. Collectively, results of the present study indicated that BTK suppressed TPA‑induced MMP‑9 expression and cell invasion/migration by activating the MAPK or IκB kinase/NF‑κB/activator protein‑1 pathway. The results clarify the mechanism of action of BTK in cancer cell metastasis by regulating MMP‑9 expression in MCF‑7 cells.

Sirtuin 6 (Sirt6) is important for maintaining kidney homeostasis and function. Cd exposure increases the risk of developing kidney diseases. However, the role of Sirt6 in kidney disease mechanisms is unclear. Here, we evaluated the role of Sirt6 in Cd-induced kidney toxicity. After Cd exposure, p62/sequestosome-1 (SQSTM1), an autophagy substrate, accumulated in mouse kidney mesangial cells in monomeric and polyubiquitinated (polyUb) forms. Sirt6 accumulated in response to Cd treatment at concentrations below the half-maximal inhibitory concentration and decreased after 12 h of treatment. Sirt6 and p62 co-localized in the nucleus and redistributed to the cytosol after Cd treatment. Sirt6 was mainly present in nuclei-rich membrane fractions. Sirt6 interacted with p62. Ub, and microtubule-associated protein light chain 3 (LC3). Knockdown of p62 promoted Sirt6 nuclear accumulation and inhibited apoptosis. Sirt6 overexpression altered levels of polyUb-p62 and apoptosis. At earlier times during Cd treatment, polyubiquitination of p62 and apoptosis were reduced. Cytoplasmic translocation of Sirt6 occurred later, with increased polyubiquitination of p62 and apoptosis. Bafilomycin 1 (BaF1) treatment promoted cytosolic Sirt6 accumulation, increasing cell death. Silencing autophagy related 5 (Atg5) increased nuclear Sirt6 levels, reduced polyUb-p62, and inhibited cell death, indicating that autophagy was necessary for Sirt6 redistribution. Cd resistance was associated with reduced polyUb-p62 and persistent Sirt6 expression. Cd treatment in mice for 4 weeks promoted p62, Sirt6, and LC3-II accumulation, inducing apoptosis in kidney tissues. Overall, our findings show that polyUb-p62 targeted Sirt6 to autophagosomes, playing a crucial role in Cd-induced cell death and kidney damage.

Ischemic osteonecrosis (ION) can produce permanent deformity and osteoarthritis in the femoral head and other joints. No biologic treatment has been established, and the molecular mechanisms involved in the pathogenesis of ION have not been elucidated. In this work, we found that treatment with sirtuin6 (Sirt6) suppressed inflammatory cytokines, bone resorption, progression of osteoarthritis, and reduced bone deformity in an ION mouse model. We used a deacetylase mutant adenovirus to confirm that those effects were caused by the deacetylase function of Sirt6. Among the osteoclastogenic factors of osteoblasts, only the receptor activator of NF-κb ligand (RANKL) level changed in response to Sirt6 knockout in primary osteoblasts. In particular, the vitamin D receptor physically interacted with Sirt6 and induced recruitment of Sirt6 around RANKL promoters. Finally, Tg mice overexpressing Sirt6 resisted osteocyte death, bone resorption, and progression of osteoarthritis after ischemic surgery, whereas osteoblast/osteocyte-specific Sirt6 knockout mice showed aggravated bone loss and severe deformity. Our findings demonstrate that administration of Sirt6 prevents bone loss and osteoarthritis in ischemic conditions. Activation of Sirt6 in osteoblasts/osteocytes could be a new therapeutic approach to treating ION of the femoral head and other bone regions. © 2020 American Society for Bone and Mineral Research (ASBMR)., (© 2020 American Society for Bone and Mineral Research (ASBMR).)

Signal transducer and activator of transcription 3 (STAT3) is crucial for the pathogenesis of psoriasis. Studies describe pleiotropic roles for a glycolytic enzyme pyruvate kinase M2 (PKM2) as a nuclear kinase of STAT3. However, little is known about the function of PKM2 in T helper type 17 cells in association with STAT3. In this study, we investigated whether and how SIRT2 deacetylase regulated the protein kinase function of PKM2 in T helper type 17 cell‒mediated inflammatory responses in psoriasis. Sirt2 knockout mice and wild-type littermates had psoriatic dermatitis induced by topical treatment of imiquimod or intradermal injection of recombinant IL-23. An initial downregulation of SIRT2 and an increase in PKM2 acetylation and STAT3 phosphorylation were observed in psoriasiform lesions of mice. SIRT2 directly interacted with and deacetylated PKM2 to suppress STAT3 phosphorylation. Consequently, psoriasiform skin inflammation was aggravated in Sirt2 knockout mice. Conversely, genetic re-expression of Sirt2 or pharmacological blockade of PKM2 decreased the disease severity. Flow cytometric analysis of skin tissues of Sirt2 knockout mice showed enhanced infiltration of T helper type 17 cells. Ex vivo experiments showed that SIRT2 deficiency accelerated T helper type 17 cell differentiation with the concomitant production of IL-17A and IL-22. The results suggest SIRT2-mediated PKM2 deacetylation as an effective option for psoriasis therapy., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

An easily accessible colorimetric and fluorescence probe 4-((3-chloro-1,4-dioxo-1,4-dihydronaphthalen-2-yl)amino)benzenesulfonamide ( 4CBS ) was successfully developed for the selective and sensitive detection of Sn 2+ in an aqueous solution. The sensing mechanism involves reduction of -C═O into -C-OH groups in 4CBS upon the addition of Sn 2+ , which initiates the fluorescence turn-on mode. A better linear relationship was achieved between fluorescence intensity and Sn 2+ concentration in the range of 0-62.5 μM, with a detection limit (LOD) of 0.115 μM. The binding mechanism of 4CBS for Sn 2+ was confirmed by Fourier transform infrared analysis, NMR titrations, and mass (electrospray ionization) spectral analysis. Likewise, the proposed sensing mechanism was supported by quantum chemical calculations. Moreover, bioimaging studies demonstrated that the chemosensing probe 4CBS is an effective fluorescent marker for the detection of Sn 2+ in living cells and zebrafish. Significantly, 4CBS was able to discriminate between Sn 2+ in human cancer cells and Sn 2+ in normal live cells.

Cholestasis is a pathological condition involving blockage of bile flow that results in hepatotoxicity, inflammation, and fibrosis. Although recent studies have shown that histone deacetylases (HDACs) are involved in the progression of fibrosis in various organs, the role of HDAC8 on liver fibrosis has until now remained unexplored. This study presents a newly-synthesized, selective HDAC8 inhibitor SPA3014 composed of a vinyl disulfide-sulfoxide core, and evaluates its therapeutic efficacy against cholestatic liver injury and fibrosis in bile duct-ligated (BDL) mice. We first observed the increase in HDAC8 protein levels in mice with BDL and patients with cholestatic liver disease. Mice with BDL that were pretreated with SPA3014 had lower liver damage and fibrosis, based on gross examination, histopathologic findings, and biochemical analyses, than did vehicle-treated mice. Studies with LX-2 human hepatic stellate cells showed that SPA3014 exerted protective effects by inhibiting TGF-β-mediated activation of MAPK-Smad2/3 and JAK2-STAT3 pathways and by upregulating PPARγ expression. Overall, these results strongly suggest that HDAC8 inhibition constitutes a new therapeutic strategy for treatment of cholestatic liver injury., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Ursolic acid (UA) possesses various pharmacological activities, such as antitumorigenic and anti-inflammatory effects. In the present study, we investigated the mechanisms underlying the effects of UA against esophageal squamous cell carcinoma (ESCC) (TE-8 cells and TE-12 cells). The cell viability assay showed that UA decreased the viability of ESCC in a dose-dependent manner. In the soft agar colony formation assay, the colony numbers and size were reduced in a dose-dependent manner after UA treatment. UA caused the accumulation of vacuoles and LC3 puncta, a marker of autophagosome, in a dose-dependent manner. Autophagy induction was confirmed by measuring the expression levels of LC3 and p62 protein in ESCC cells. UA increased LC3-II protein levels and decreased p62 levels in ESCC cells. When autophagy was hampered using 3-methyladenine (3-MA), the effect of UA on cell viability was reversed. UA also significantly inhibited protein kinase B (Akt) activation and increased p-Akt expression in a dose-dependent manner in ESCC cells. Accumulated LC3 puncta by UA was reversed after wortmannin treatment. LC3-II protein levels were also decreased after treatment with Akt inhibitor and wortmannin. Moreover, UA treatment increased cellular reactive oxygen species (ROS) levels in ESCC in a time- and dose-dependent manner. Diphenyleneiodonium (an ROS production inhibitor) blocked the ROS and UA induced accumulation of LC3-II levels in ESCC cells, suggesting that UA-induced cell death and autophagy are mediated by ROS. Therefore, our data indicate that UA inhibits the growth of ESCC cells by inducing ROS-dependent autophagy.