Primary cilium, microtubule-based sensory organelle that has emerged as a central player in coordinating numerous signaling pathways. Although primary cilia are known to regulate cellular signaling and energy metabolism, the relationship between these roles in the context of ciliopathies and brown adipose tissue (BAT) dysfunction remains poorly understood. To elucidate the role of primary cilia in BAT, we generated Ucp1-Cre;Ift88flox/flox mice with BAT-specific ciliary loss. There were no significant differences in body size, weight, or BAT weight relative to body weight between P0 Ucp1-Cre;Ift88flox/flox and P0 Ucp1-Cre;Ift88+/+ pups. Embryos examined at E14.5 and E18.5 also showed no discernible differences in size, morphology, or histology. However, P0 Ucp1-Cre;Ift88flox/flox pups exhibited neonatal lethality caused by defective thermogenesis, despite preserved Ucp1 expression. These mice displayed markedly reduced ketone body levels in both BAT and serum, accompanied by downregulation of Hmgcs2 , a key enzyme in ketogenesis. Loss of primary cilia in BAT suppressed ketogenesis and increased ROS production through HMGCS2 downregulation, ultimately impairing non-shivering thermogenesis. Remarkably, neonatal lethality of Ucp1-Cre;Ift88flox/flox pups was completely rescued by thermoneutral housing or β-hydroxybutyrate supplementation. Our findings identified a previously unrecognized mechanism by which primary cilia regulate non-shivering, UCP1-independent thermogenesis via ketogenesis.
Premature ovarian insufficiency (POI) is characterized by impaired ovarian function before the age of 40 and is closely associated with granulosa cell dysfunction, excessive oxidative stress, inflammation, and accelerated depletion of the ovarian follicular reserve. Oleanolic acid (OA), a naturally occurring pentacyclic triterpenoid found in several medicinal plants, has been reported to exert antioxidant and anti-inflammatory effects in various disease models. Although previous studies have suggested potential protective effects of OA in ovarian granulosa cells under oxidative stress conditions, the molecular mechanisms underlying these effects remain largely unclear. Therefore, this study investigated whether OA protects against oxidative stress-induced granulosa cell dysfunction and ovarian injury through modulation of the SIRT1/NF-κB signaling pathway. Human KGN cells and mouse primary granulosa cells were exposed to hydrogen peroxide (H2O2) to establish an in vitro oxidative stress model. Cells were treated with OA, and cell viability, intracellular ROS accumulation, antioxidant enzyme activity, antioxidant protein expression, NF-κB signaling activation, inflammatory cytokine expression, and follicular development-related gene expression were analyzed. To determine whether SIRT1 mediates the effects of OA, SIRT1 knockdown was performed using shRNA. In vivo, female mice were subjected to 3-nitropropionic acid (3-NP)-induced oxidative ovarian injury and treated with OA. Ovarian morphology, follicle counts, serum anti-Müllerian hormone (AMH) levels, and ovarian SIRT1/NF-κB expression were evaluated. OA significantly improved granulosa cell viability under H2O2-induced oxidative stress by reducing intracellular ROS accumulation and restoring antioxidant defense through increased SOD and catalase activity and upregulation of SOD2, catalase, and GPx-1 expression. OA also inhibited NF-κB p65 nuclear translocation, reduced phosphorylation of NF-κB p65 and IκBα, and decreased the expression of inflammatory mediators including NLRP3, TNF-α, IL-1β, and IL-6. In addition, OA restored the expression of genes associated with granulosa cell function and follicular development. Mechanistically, OA increased SIRT1 expression, whereas SIRT1 knockdown attenuated the inhibitory effect of OA on NF-κB signaling. In the 3-NP-induced ovarian injury model, OA preserved follicular development, reduced follicular atresia, restored serum AMH levels, increased ovarian SIRT1 expression, and suppressed NF-κB activation. OA protects granulosa cells and ovarian tissue from oxidative stress-induced inflammatory injury by restoring SIRT1 expression and suppressing NF-κB signaling in a SIRT1-dependent manner. These findings suggest that OA may help preserve granulosa cell function, support follicular development, and maintain ovarian reserve under oxidative stress-associated ovarian dysfunction.
Inflammation-induced placental dysfunction is a major contributor to pregnancy complications. Activation of NF-κB and NLRP3 inflammasome pathways in the placenta is a key driver of this pathology. Decursinol, a natural coumarin derivative from Angelica gigas, possesses anti-inflammatory properties; however, its effect on placental inflammation remains unclear. Therefore, in this study, we investigated the protective effects of decursinol against lipopolysaccharide (LPS)-induced placental inflammation and trophoblast dysfunction and explored the underlying molecular mechanisms. Decursinol significantly inhibited LPS-induced NLRP3 inflammasome activation and NF-κB/p65 signaling in Sw.71 human trophoblast cells, reducing interleukin-1β secretion and pro-inflammatory gene expression. It restored the trophoblast invasive capacity and preserved mesenchymal marker expression suppressed by LPS. It also improved the fetal and placental weights, restored the placental architecture, and attenuated placental NLRP3 inflammasome activation and cytokine expression in vivo. Mechanistically, decursinol preserved the mitochondrial homeostasis, reduced mitochondrial reactive oxygen species levels, and upregulated antioxidants and mitochondrial biogenesis-related gene levels, exerting effects comparable to those of mitochondria-targeted antioxidant Mito-TEMPO. These findings suggest that decursinol protects against LPS-induced trophoblast dysfunction and adverse pregnancy outcomes by preserving mitochondrial functions and suppressing NLRP3/NF-κB-mediated inflammation. Overall, our results highlight decursinol as a promising therapeutic candidate for inflammation-associated pregnancy complications.
Reactive Oxygen Species (ROS) accumulation disrupts cellular homeostasis, leading to lipid peroxidation, mitochondrial dysfunction, DNA damage, and apoptosis. Sestrin2 (Sesn2) is a critical antioxidant protein that regulates intracellular oxidative stress and protects cells from oxidative damage and apoptosis. However, the role of Sesn2 in ovarian reproductive function remains unclear. In this study, we examined Sesn2 expression in response to oxidative stress using granulosa-like KGN cells derived from human ovarian granulosa cell tumors, mouse granulosa cells, and an oxidative stress mouse model. Additionally, we investigated the protective Sesn2 functions and its mechanisms of action in promoting granulosa cell survival. The results showed that Sesn2 expression markedly increased in granulosa cells exposed to hydrogen peroxide (H2O2) and in oxidative stress models induced by 3-nitropropionic acid (3-NP). Oxidative stress in ovarian granulosa cells increases ROS levels, decreases cell viability, and triggers apoptosis. Sesn2 silencing further aggravates granulosa cell damage, whereas targeting Sesn2 under oxidative stress conditions reduces ROS levels and modulates apoptosis through the p53/Caspase-3 signaling pathway. These findings highlight the pivotal role of Sesn2 in protecting cells against ROS-induced damage, preserving follicular health, and supporting ovarian function and reproductive capacity.
Endometrial cancer, a common gynecological malignancy, poses significant clinical challenges, particularly in advanced or recurrent cases. TANK-binding kinase 1 (TBK1), a serine/threonine kinase, plays crucial roles in inflammation and immunity by activating nuclear factor (NF)-kappa B and interferon regulatory factor 3. However, its specific roles in endometrial cancer remain unknown. In this study, we aimed to investigate the anti-cancer effects and underlying mechanisms of amlexanox, a TBK1 inhibitor, against endometrial cancer. The main genetic mutations in TBK1 were found to be mRNA downregulation and missense mutations. Kaplan-Meier plotter analysis revealed that low TBK1 expression was associated with a good prognosis in patients with uterine corpus endometrial carcinoma (UCEC). In vitro experiments demonstrated that TBK1 knockdown or amlexanox significantly inhibited the proliferation, cell cycle progression, and migration of endometrial cancer cells. Furthermore, the inhibitory effects of targeting TBK1 on cancer cell proliferation and migration were mediated by the protein kinase B (AKT)/NF-kappa B signaling pathway. Xenograft experiments revealed that both amlexanox treatment and TBK1 knockdown effectively suppressed the tumor growth. Overall, this study highlights the potent anti-cancer effects of amlexanox against endometrial cancer by modulating AKT/NF-kappa B signaling, thus providing a new avenue for the development of novel TBK1-targeting therapeutic strategies for UCEC.
Introduction:Metabolic dysfunction-associated steatotic liver disease has limited treatment options, posing a serious global health challenge. Epicatechin (EC), a natural flavonoid, exhibits therapeutic potential; however, its clinical utility is hindered by its low solubility and limited bioavailability. Therefore, in this study, we developed liver-targeted EC-loaded galactosylated poly(lactic-co-glycolic acid)-polyethylene glycol nanoparticles (EC@PLGA-PEG-GAL NPs) with high therapeutic efficacy. Methods:EC@PLGA-PEG-GAL NPs were synthesized, and their physicochemical properties, biocompatibility, and hepatocyte-targeted cellular uptake were characterized. The therapeutic efficacy of the NPs was assessed in high-fat diet (HFD)-fed mice, evaluating metabolic dysfunction and hepatic steatosis. Mechanistic studies were performed to investigate the effects on autophagic flux and mitochondrial function. Results:The EC@PLGA-PEG-GAL NPs exhibited improved EC solubility, sustained drug release, and low cytotoxicity. In HFD-fed mice, administration of EC@PLGA-PEG-GAL NPs significantly ameliorated hepatic steatosis, reduced insulin resistance, and alleviated metabolic dysfunction, without causing toxicity. Mechanistically, these NPs restored the autophagic flux by activating the AMP-activated protein kinase pathway and inhibiting mechanistic target of rapamycin complex 1 signaling, thereby enhancing ubiquitinated protein clearance. They also alleviated mitochondrial dysfunction by enhancing the membrane potential, reducing the reactive oxygen species levels, and promoting mitochondrial biogenesis. Conclusion:Our findings highlight EC@PLGA-PEG-GAL NPs as promising liver-targeted nanotherapeutics simultaneously modulating autophagy and mitochondrial functions in metabolic dysfunction-associated steatotic liver disease.
Introduction: Metabolism-associated fatty liver disease (MAFLD) is a global health concern because of its association with obesity, insulin resistance, and other metabolic abnormalities. Methylsulfonylmethane (MSM), an organic sulfur compound found in various plants and animals, exerts antioxidant and anti-inflammatory effects. Here, we aimed to assess the anti-obesity activity and autophagy-related mechanisms of Methylsulfonylmethane.Method: Human hepatoma (HepG2) cells treated with palmitic acid (PA) were used to examine the effects of MSM on autophagic clearance. To evaluate the anti-obesity effect of MSM, male C57/BL6 mice were fed a high-fat diet (HFD; 60% calories) and administered an oral dose of MSM (200 or 400 mg/kg/day). Moreover, we investigated the AMP-activated protein kinase (AMPK)/mechanistic target of rapamycin complex 1 (mTORC1)/UNC-51-like autophagy-activating kinase 1 (ULK1) signaling pathway to further determine the underlying action mechanism of MSM.Results: Methylsulfonylmethane treatment significantly mitigated PA-induced protein aggregation in human hepatoma HepG2 cells. Additionally, Methylsulfonylmethane treatment reversed the PA-induced impairment of autophagic flux. Methylsulfonylmethane also enhanced the insulin sensitivity and significantly suppressed the HFD-induced obesity and hepatic steatosis in mice. Western blotting revealed that Methylsulfonylmethane improved ubiquitinated protein clearance in HFD-induced fatty liver. Remarkably, Methylsulfonylmethane promoted the activation of AMPK and ULK1 and inhibited mTOR activity.Conclusion: Our study suggests that MSM ameliorates hepatic steatosis by enhancing the autophagic flux via an AMPK/mTOR/ULK1-dependent signaling pathway. These findings highlight the therapeutic potential of MSM for obesity-related MAFLD treatment.
Abstract Purpose Recent studies indicate that microRNAs (miRNAs) play essential roles in cellular development, homeostasis, and response. However, the function of miRNA in the senescence of human lymphatic endothelial cells (HLECs) remains unclear. We aimed to find miRNAs related to HLECs’ aging and elucidate miRNAs’ molecular mechanism. Methods HLECs were cultured, and total RNA was harvested from the cells. Then, MiRNA screening was performed, with targeted miRNAs selected using quantitative polymerase chain reaction (qPCR). To evaluate the effect of miR-193b, HLECs were treated with a mimic and inhibitor, and tube formation was investigated. We used a luciferase assay to analyze the expression of CCND1, a well-known gene involved in cell passage, in response to miR-193b. Results Seven miRNAs were primarily screened. Among them, miR-193b-3p showed a high affinity for HLECs. Transfection of the mir-193b-3p mimic decreased cell proliferation and affected tube formation. CCND1 mRNA and protein levels also were decreased by the cell-transfected mir-193b-3p mimic. Conclusion This study provides the first evidence that miR-193b-3p represses cell proliferation and regulates CCND1, which may play an important role in lymphangiogenesis.
BackgroundObesity, a serious threat to public health, is linked to chronic metabolic complications including insulin resistance, type-2 diabetes, and metabolic dysfunction-associated fatty liver disease (MAFLD). Current obesity medications are challenged by poor effectiveness, poor patient compliance, and potential side effects. Verapamil is an inhibitor of L-type calcium channels, FDA-approved for the treatment of hypertension. We previously investigated the effect of verapamil on modulating autophagy to treat obesity-associated lipotoxicity. This study aims to develop a verapamil transdermal patch and to evaluate its anti-obesity effects.MethodsVerapamil is loaded in biomimetic vascular bundle-like carboxymethyl pullulan-based supramolecular hydrogel patches cross-linked with citric acid and glycerol linkages (CLCMP). The investigation was then carried out to determine the therapeutic effect of verapamil-loaded CLCMP (Vera@CLCMP) on diet-induced obese mice.ResultsVera@CLCMP hydrogel patches with hierarchically organized and anisotropic pore structures not only improved verapamil bioavailability without modifying its chemical structure but also enhanced verapamil release through the stratum corneum barrier. Vera@CLCMP patches exhibit low toxicity and high effectiveness at delivering verapamil into the systemic circulation through the dermis in a sustained manner. Specifically, transdermal administration of this patch into diet-induced obese mice drastically improved glucose tolerance and insulin sensitivity and alleviated metabolic derangements associated with MAFLD. Furthermore, we uncovered a distinct molecular mechanism underlying the anti-obesity effects associated with the hepatic NLR family pyrin domain-containing 3 (NLRP3) inflammasome and autophagic clearance by the vera@CLCMP hydrogel patches.ConclusionThe current study provides promising drug delivery platforms for long-term family treatment of chronic diseases, including obesity and metabolic dysfunctions.
Chronic exposure to bile acid in the liver due to impaired bile flow induces cholestatic liver disease, resulting in hepatotoxicity and liver fibrosis. Sestrin2, a highly conserved, stress-inducible protein, has been implicated in cellular responses to multiple stress conditions and the maintenance of cellular homeostasis. However, its role in cholestatic liver injury is not fully understood. In this study, we investigated the role of hepatic Sestrin2 in cholestatic liver injury and its underlying mechanisms using in vivo and in vitro approaches. Hepatic Sestrin2 expression was upregulated by activating transcription factor 4 (ATF4) and CCAAT/enhancer-binding protein-β (C/EBP-β) after treatment with bile acids and correlated with endoplasmic reticulum (ER) stress responses. Bile-duct ligation (BDL)-induced hepatocellular apoptosis and liver fibrosis were exacerbated in Sestrin2-knockout ( Sesn2 −/− ) mice. Moreover, Sestrin2 deficiency enhanced cholestasis-induced hepatic ER stress, whereas Sestrin2 overexpression ameliorated bile acid-induced ER stress. Notably, the mammalian target of rapamycin (mTOR) inhibitor rapamycin and the AMP-activated protein kinase (AMPK) activator AICAR reversed bile acid-induced ER stress in Sestrin2-deficient cells. Furthermore, Sestrin2 deficiency promoted cholestasis-induced hepatic pyroptosis by activating NLRP3 inflammasomes. Thus, our study provides evidence for the biological significance of Sestrin2 and its relationship with cholestatic liver injury, suggesting the potential role of Sestrin2 in regulating ER stress and inflammasome activation during cholestatic liver injury.
The NAD+-dependent deacetylase Sirt1 is known to modulate metabolism, inflammation, and aging. It has been reported that Sirt1 regulates differentiation and function of innate immune cells and T cells. However, the role of Sirt1 in B cell functions has not been well studied. The present study aimed to determine the role of Sirt1 in antigen presentation function of B cells. First, we investigated the effects of Sirt1 activator/inhibitor and Sirt1 deficiency on expression of major components (Ii, DM, DO, and MHC II) of the MHC II antigen presentation pathway in B cells, and we determined whether antigen presentation function of B cells is dependent on Sirt1 using an experiment regarding CD4+ OT-II T cell responses to OVA-pulsed Sirt1-deficient B cells or OVA-pulsed Sirt1 activator/inhibitor-stimulated B cells in vitro co-culture. Expression of all the components in B cells and CD4+ OT-II T differentiation to CD4+TNF-α+ (Th1), CD4+IL-17+ (Th17), and CD4+IL-21+ (Tfh) cells were diminished in the case of Sirt1 inhibitor-treated B cells or Sirt1-deficient B cells, while Sirt1 activator increased the expression and the differentiation. Next, we found that Sirt1 deacetylates CIITA, a key transcription factor of transcription of the major components in the MHC II antigen presentation pathway, in B cells. In addition, we revealed that Sirt1 is required for CIITA expression. Taken together, we conclude that Sirt1 is essential for antigen presentation by B cells, and this might be caused by induction of CIITA expression and deacetylation of CIITA. Supported by grants from NRF (2016R1D1A1B04935588, 2017R1A6A1A03015713)
Pathological maternal inflammation and abnormal placentation contribute to several pregnancy-related disorders, including preterm birth, intrauterine growth restriction, and preeclampsia. TANK-binding kinase 1 (TBK1), a serine/threonine kinase, has been implicated in the regulation of various physiological processes, including innate immune response, autophagy, and cell growth. However, the relevance of TBK1 in the placental pro-inflammatory environment has not been investigated. In this study, we assessed the effect of TBK1 inhibition on lipopolysaccharide (LPS)-induced NLRP3 inflammasome activation and its underlying mechanisms in human trophoblast cell lines and mouse placenta. TBK1 phosphorylation was upregulated in the trophoblasts and placenta in response to LPS. Pharmacological and genetic inhibition of TBK1 in trophoblasts ameliorated LPS-induced NLRP3 inflammasome activation, placental inflammation, and subsequent interleukin (IL)-1 production. Moreover, maternal administration of amlexanox, a TBK1 inhibitor, reversed LPS-induced adverse pregnancy outcomes. Notably, TBK1 inhibition prevented LPS-induced NLRP3 inflammasome activation by targeting the mammalian target of rapamycin complex 1 (mTORC1). Thus, this study provides evidence for the biological significance of TBK1 in placental inflammation, suggesting that amlexanox may be a potential therapeutic candidate for treating inflammation-associated pregnancy-related complications.
Emerging evidence indicates that aberrant maternal inflammation is associated with several pregnancy-related disorders such as preeclampsia, preterm birth, and intrauterine growth restriction. Sirtuin1 (SIRT1), a class III histone deacetylase, is involved in the regulation of various physiopathological processes including cellular inflammation and metabolism. However, the effect of SIRT1 on the placental proinflammatory environment remains to be elucidated. In this study, we investigated the effect of SIRT1 on lipopolysaccharide (LPS)-induced NLRP3 inflammasome activation and its underlying mechanisms in human first-trimester trophoblasts (Sw.71 and HTR-8/SVneo cells). Treatment with LPS elevated SIRT1 expression and induced NLRP3 inflammasome activation in mouse placental tissues and human trophoblasts. Knockdown of SIRT1 enhanced LPS-induced NLRP3 inflammasome activation, inflammatory signaling, and subsequent interleukin (IL)-1β secretion. Furthermore, knockdown of NLRP3 considerably attenuated the increase of IL-1β secretion in SIRT1-knockdown cells treated with LPS. Moreover, SIRT1 inhibited LPS-induced NLRP3 inflammasome activation by reducing oxidative stress. This study revealed a novel mechanism via which SIRT1 exerts anti-inflammatory effects, suggesting that SIRT1 is a potential therapeutic target for the prevention of inflammation-associated pregnancy-related complications.
PROBLEM:Maternal obesity induces elevated saturated fatty acid palmitate levels in the blood and causes pregnancy complications such as gestational diabetes, preeclampsia, fetal growth abnormalities, and stillbirth. Sestrin2, a highly conserved stress-inducible protein, is involved in the cellular responses of various stress conditions and homeostatic regulation. However, the effects of Sestrin2 on trophoblast cells have not yet been investigated. Here, we investigated the role of Sestrin2 in palmitate-induced lipotoxicity and its underlying mechanisms in human first-trimester trophoblast cells (Sw.71).METHOD OF STUDY:Mouse placental tissues were obtained from low-fat diet-fed mice (n = 14) and high-fat diet-fed mice (n = 14) at gestation day 17.5. Sw.71 cells were treated with palmitate or bovine serum albumin as vehicle controls. The role of Sestrin2 in palmitate-induced lipotoxicity was examined by immunocytochemistry, immunoblot analysis, quantitative real-time PCR, and invasion assay.RESULTS:Expression of placental Sestrin2 was elevated in high-fat diet-fed dams compared to that of low-fat diet-fed dams. Prolonged treatment of Sw.71 cells with palmitate-induced endoplasmic reticulum (ER) stress-dependent expressions of Sestrin2 protein and mRNA, and the treatment also triggered apoptosis. Knockdown of Sestrin2 increased palmitate-mediated ER stress, inflammatory signaling, and apoptosis. Furthermore, Sestrin2 suppressed impaired trophoblast invasion caused by palmitate and attenuated palmitate-induced ER stress and inflammation via AMPK/mTORC1 pathways.CONCLUSION:Our study provides the relationship between Sestrin2, AMPK/mTORC1 pathway, and trophoblast function, suggesting that Sestrin2 may be a novel potential therapeutic target for the prevention of pregnancy complications.
Sirt1 is a NAD+-dependent deacetylase that is well known to control aging and metabolism. Many reports show that Sirt1 regulates innate and adaptive immune responses. Among them, several studies have examined the role of Sirt1 in antigen processing and presentation in dendritic cells. The aim of the present study is to determine the role of Sirt1 in antigen presentation in B cells. First, we examined the expression of major components of the MHCII antigen presentation pathway (Ii, HLA-DM, HLA-DO, and MHCII) and maturation markers (CD40, CD80, and CD86) in Sirt1-deficient B cells using qRT-PCR and flow cytometric analysis. All the components and the markers expressions were lower in Sirt1-deficient B cells than wild-type (WT). To determine whether B cell APC function is dependent on Sirt1, we performed experiments regarding CD4+ OT-II T cell responses to OVA-pulsed Sirt1-deficient B cells or WT B cells in vitro co-culture. CD4+CD69+, CD4+TNF-α+, and CD4+IL-17+ T cells were decreased in Sirt1-deficient B cells compared with that of WT. In addition, T-bet/RORγt mRNA expression and TNF-α/IL-17 secretion were diminished in Sirt1-deficient B cells in the culture. Collectively, these results indicate that Sirt1 in B cells is required for expression of components of MHCII antigen presentation pathway and APC function to activate and functionally differentiate CD4+ T cells.
Oncogenic activation of the mammalian target of rapamycin complex 1 (mTORC1) leads to endometrial cancer cell growth and proliferation. Sestrin2 (SESN2), a highly conserved stress-inducible protein, is involved in homeostatic regulation via inhibition of reactive oxygen species (ROS) and mTORC1. However, the role of SESN2 in human endometrial cancer remains to be investigated. Here, we investigated expression, clinical significance, and underlying mechanisms of SESN2 in endometrial cancer. SESN2 was upregulated more in endometrial cancer tissues than in normal endometrial tissues. Furthermore, upregulation of SESN2 statistically correlated with shorter overall survival and disease-free survival in patients with endometrial cancer. SESN2 expression strongly correlated with mTORC1 activity, suggesting its impact on prognosis in endometrial cancer. Additionally, knockdown of SESN2 promoted cell proliferation, migration, and ROS production in endometrial cancer cell lines HEC-1A and Ishikawa. Treatment of these cells with mTOR inhibitors reversed endometrial cancer cell proliferation, migration, and epithelial–mesenchymal transition (EMT) marker expression. Moreover, in a xenograft nude mice model, endometrial cancer growth increased by SESN2 knockdown. Thus, our study provides evidence for the prognostic significance of SESN2, and a relationship between SESN2, the mTORC1 pathway, and endometrial cancer growth, suggesting SESN2 as a potential therapeutic target in endometrial cancer.
It has been suggested that oxidative stress involving reactive oxygen species (ROS) induces granulosa cell apoptosis, leading to follicular atresia, and that T‑lymphokine‑activated killer cell‑originated protein kinase (TOPK) suppresses cancer cell apoptosis induced by several stimuli. However, it remains to be determined whether TOPK affects oxidative stress‑induced granulosa cell apoptosis. The present study demonstrates that TOPK inhibition increases human granulosa COV434 cell apoptosis induced by hydrogen peroxide (H2O2). Co‑treatment with the TOPK inhibitor, OTS514, in combination with H2O2 increased p53 acetylation and its expression, whereas it decreased Sirtuin 1 (SIRT1) expression, contributing to the promotion of apoptosis. In addition, the SIRT1 activator, resveratrol, or the SIRT1 inhibitor, Ex527, reduced or elevated H2O2‑induced COV434 cell apoptosis, respectively. Furthermore, the p53 inhibitor, Pifithrin‑μ, diminished the augmentation in poly(ADP‑ribose) polymerase (PARP) cleavage induced by OTS514 plus H2O2, while the Mdm2 antagonist, Nutlin 3, increased PARP cleavage. Moreover, OTS514 further decreased the SIRT1 transcriptional activity decreased by H2O2, but promoted the H2O2‑induced p53 or p21 transcriptional activity. Notably, the expression of exogenous p53 reduced SIRT1 transcriptional activity. Taken together, the findings of the present study demonstrate that TOPK inhibition promotes p53‑mediated granulosa cell apoptosis through SIRT1 downregulation in response to H2O2. Therefore, it can be concluded that TOPK suppresses H2O2‑induced apoptosis through the modulation of the p53/SIRT1 axis, suggesting a potential role of TOPK in the regulation of human granulosa cell apoptosis, leading to the promotion of abnormal follicular development.
Sirt1, also known as the longevity gene, is an NAD+-dependent class III histone deacetylase that has been extensively studied in multiple areas of research including cellular metabolism, longevity, cancer, autoimmunity, and immunity. However, little is known about the function of Sirt1 in B cells. This study aimed to investigate the role of Sirt1 in the expression pattern of mRNAs in the resting B cells of mice. CD19+ B cell-specific inducible Sirt1 knockout (KO) mice were divided into tamoxifen-treated Sirt1 KO group (S19T) or control group (S19). mRNAs extracted from resting B cells of both groups were analyzed for differentially expressed genes (DEG) using microarray. DEG analysis showed significant differential expression of 20 genes, of which Hspa1a and Hspa1b showed the highest fold change (FC) in S19T compared with S19 (p value < 0.01 and FC > 3). Further, Kyoto Encyclopedia of Genes and Genomes analysis identified pathways associated with diseases, organismal systems, and antigen processing and presentation. Additionally, the pathways known to involve Hspa1a and Hspa1b were also activated in the S19T group. On the other hand, after in vitro stimulation with lipopolysaccharide, cell viability and IgM production were significantly decreased in Sirt1 KO B cells, while expressions of TNF-α, IL-6, and IL-10 were increased. In summary, our study reveals that Sirt1 may maintain the quiescent state in resting B cells by suppressing the increase of Hspa1a and Hspa1b. This work provides a foundation for further studies on the functional roles of Sirt1 in B cells.
Red emitting europium (III) complexes Eu(TFAAN)3(P(Oct)3)3 (TFAAN = 2-(4,4,4-Trifluoroacetoacetyl)naphthalene, P(Oct)3 = trioctylphosphine) chelated on carboxymethyl dextran coated superparamagnetic iron oxide nanoparticles (CMD-SPIONs) was synthesized and the step wise synthetic process was reported. All the excitation spectra of distinctive photoluminesces were originated from f-f transition of EuIII with a strong red emission. The emission peaks are due to the hypersensitive transition 5D0→7F2 at 621 nm and 5D0→7F1 at 597 nm, 5D0→7F0 at 584 nm. No significant change in PL properties due to addition of CMD-SPIONs was observed. The cytotoxic effects of different concentrations and incubation times of Eu(TFAAN)3(P(Oct)3)3 chelated CMD-SPIONs were evaluated in HEK293T and HepG2 cells using the WST assay. The results imply that Eu(TFAAN)3(P(Oct)3)3 chelated CMD-SPIONs are not affecting the cell viability without altering the apoptosis and necrosis in the range of 10 to 240 μg/mL concentrations.
Obesity and overweight, the most serious health problems, are associated with chronic metabolic complications such as type 2 diabetes, insulin resistance, and nonalcoholic fatty liver disease (NAFLD). However, current pharmacological therapies for obesity are challenged by potential side effects, low effectiveness, and low aqueous solubility, which limit their clinical application. Here, we develop nifedipine-loaded nanoparticles (NFD-NPs) that alleviate obesity-related metabolic dysfunction to be used as instruments for translational medicine. Nanoparticles (NPs) composed of poly (lactic-co-glycolic acid) (PLGA) not only enhance water solubility of hydrophobic nifedipine (NFD), a calcium channel blocker, without modifying the chemical structure of NFD for intravenous administration, but also allow prolonged release of NFD in vivo. NFD-NPs do not show cytotoxicity and reduce palmitate-induced protein inclusions and endoplasmic reticulum stress in human hepatoma HepG2 cells. Importantly, tail-vein injection of NFD-NPs into diet-induced obese mice results in sustained retention of NFD-NPs in the liver and suppression of metabolic derangements associated with NAFLD by enhancing autophagic clearance through Ca2+/calmodulin-dependent kinase II (CaMKII) phosphorylation, consequently decreasing diet-induced insulin resistance and improving glucose tolerance. Our findings offer new clinical tools for NP-mediated pharmaceutical strategies to treat NAFLD and its related metabolic dysfunction.