Dose dependent effect of cilostazol in induced testicular ischemia reperfusion via modulation of HIF/VEGF and cAMP/SIRT1 pathways.

Twisting of the spermatic cord is a common dangerous health problem that may be accompanied with testicular necrosis and infertility. Cilostazol (CLZ) is a selective phosphodiesterase (PDE) 3A inhibitor used for treatment of intermittent claudication. It has a great role in myocardial, spinal cord and hepatic ischaemia/reperfusion. However, till now, there are no researches evaluating its role in testicular ischaemia/reperfusion (TIR). The current work studies its capability to improve TIR induced injury with more concentration on the mechanisms involved in such effect. Four groups of animals were included: sham, TIR induced group, TIR plus CLZ low dose (10 mg/kg), TIR plus CLZ high dose (30 mg/kg). Our results proved that TIR had significant decrease of the serum ELISA of testosterone, marked disturbances in oxidative stress evaluated parameters as malondialdehyde (MDA), reduced glutathione (GSH), total antioxidant capacity (TAC), ELISA measurement of tumor necrosis factor alpha (TNFα) and interleukin 1 beta (IL1ß) inflammatory mediators, apoptotic marker (caspase3) using western blotting, immunohistochemistry of hypoxia inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF). TIR reduced the protective agents as cyclic adenosine monophosphate (cAMP) and sirtuin-1 (SIRT1) by ELISA method with marked germinal cell apoptosis. The biochemical results were confirmed by the histopathological findings that showed marked decrease in both Johnsen's score and Cosentino's score. However, treatment with CLZ significantly reversed the profound TIR damaging effects, on the basis of its anti-inflammatory, anti-oxidant, and anti-apoptotic activities with recuperation of the testicular vascularity. Modulation of HIF/VEGF and cAMP/SIRT1 pathways showed a great role in mediating such effect.

Genome-wide histone acetylation analysis reveals altered transcriptional regulation in the Parkinson's disease brain.

BACKGROUND: Parkinson's disease (PD) is a complex, age-related neurodegenerative disorder of largely unknown etiology. PD is strongly associated with mitochondrial respiratory dysfunction, which can lead to epigenetic dysregulation and specifically altered histone acetylation. Nevertheless, and despite the emerging role of epigenetics in age-related brain disorders, the question of whether aberrant histone acetylation is involved in PD remains unresolved. METHODS: We studied fresh-frozen brain tissue from two independent cohorts of individuals with idiopathic PD (n = 28) and neurologically healthy controls (n = 21). We performed comprehensive immunoblotting to identify histone sites with altered acetylation levels in PD, followed by chromatin immunoprecipitation sequencing (ChIP-seq). RNA sequencing data from the same individuals was used to assess the impact of altered histone acetylation on gene expression. RESULTS: Immunoblotting analyses revealed increased acetylation at several histone sites in PD, with the most prominent change observed for H3K27, a marker of active promoters and enhancers. ChIP-seq analysis further indicated that H3K27 hyperacetylation in the PD brain is a genome-wide phenomenon with a strong predilection for genes implicated in the disease, including SNCA, PARK7, PRKN and MAPT. Integration of the ChIP-seq with transcriptomic data from the same individuals revealed that the correlation between promoter H3K27 acetylation and gene expression is attenuated in PD patients, suggesting that H3K27 acetylation may be decoupled from transcription in the PD brain. Strikingly, this decoupling was most pronounced among nuclear-encoded mitochondrial genes, corroborating the notion that impaired crosstalk between the nucleus and mitochondria is involved in the pathogenesis of PD. Our findings independently replicated in the two cohorts. CONCLUSIONS: Our findings strongly suggest that aberrant histone acetylation and altered transcriptional regulation are involved in the pathophysiology of PD. We demonstrate that PD-associated genes are particularly prone to epigenetic dysregulation and identify novel epigenetic signatures associated with the disease.

The protective effects of resveratrol pretreatment in cyclophosphamide-induced rat ovarian injury: an vivo study.

OBJECTIVES: To explore whether resveratrol (Res) pretreatment could exert a protective effect on cyclophosphamide (Cy) induced ovarian toxicity in a rat model. METHODS: Twenty-four female 7-week old Sprague-Dawley rats were randomly divided into four groups: Con, administered with vehicle solutions; Cy, treated with Cy; Res + Cy, treated with Cy + Res combined; Res, treated with Res. After 21 d of treatments, the rats were euthanized and blood samples were collected to evaluate the levels of anti-Müllerian hormone (AMH). The Ovaries were processed for immunohistochemical and western blotting. RESULTS: Cy-treat caused the decrease of body weights and ovarian weight. AMH was lower in Cy group, whereas AMH levels were similar among other groups. Histomorphology showed a large number of primordial follicles were activated in Cy groups, whereas the primordial follicles were inhibited in the Res and Res + Cy groups. The expressions of Sirt1, Foxo3a were up-regulated and p53, Caspase-3, and Bax were down-regulated in Res + Cy and Res groups (p < .05). CONCLUSIONS: Res can prevent the primordial follicle activation and decrease apoptosis induced by Cy. Res may be an effective protection for ovarian function during chemotherapy, which means a new nonsurgical application for protection of ovarian reserve.

Deacetylation of FOXO4 by Sirt1 stabilizes chondrocyte extracellular matrix upon activating SOX9.

OBJECTIVE: FOXO4 has essential roles in cellular metabolism and prevents cartilage degeneration in osteoarthritis (OA). Here we aim to provide evidence that deacetylated-FOXO4 stabilizes chondrocyte (CH) extracellular matrix (ECM) related to SOX9 activation. PATIENTS AND METHODS: We used Chromatin immunoprecipitation (ChIP) and Dual-Luciferase reporter assay to verify that the FOXO4 protein activates SOX9 by binding to its promoter. We cultured human CHs with IL-1ß to cause degeneration and supplied Sirt1 protein to deacetylate FOXO4. To confirm the function of FOXO4 and SOX9 during CHs degeneration, we also used the FOXO4 and SOX9 silenced CHs by siRNA transfection as a comparison. Western blot assay was used to analyze the protein level of Sirt1, SOX9, and the acetylated condition of FOXO4. Besides, RT-PCR was used to measure the mRNA level of collagen I/II/X, aggrecan, MMP-13, and ADAMTS-5 for determining the ECM states. RESULTS: FOXO4 protein transcriptionally activates SOX9 expression by binding to its promoter. Under the IL-1ß stimulation, FOXO4 acetyl-lysine rate increased, and the SOX9 protein expression decreased, which was alleviated after the supplement of exogenic Sirt1 protein. Meanwhile, Sirt1 overexpression increased the collagen II and aggrecan and reduced the collagen I, collagen X, MMP-13, and ADAMTS-5 mRNA expression. However, the silencing of FOXO4 abolished the Sirt1 induced SOX9 expression and weakened the ECM production stability. Additionally, SOX9 silencing also alleviated the effect of the Sirt1 supplement on the degenerated CHs, though the FOXO4 was highly deacetylated. CONCLUSIONS: FOXO4 acetylation aggravates during the degeneration of CHs, and the deacetylation of FOXO4 by Sirt1 could activate the SOX9 expression and result in maintaining the ECM stability of cartilage.

Endurance Exercise-Induced Autophagy/Mitophagy Coincides with a Reinforced Anabolic State and Increased Mitochondrial Turnover in the Cortex of Young Male Mouse Brain.

Autophagy/mitophagy, a cellular catabolic process necessary for sustaining normal cellular function, has emerged as a potential therapeutic strategy against numerous obstinate diseases. In this regard, endurance exercise (EXE)-induced autophagy/mitophagy (EIAM) has been considered as a potential health-enriching factor in various tissues including the brain; however, underlying mechanisms of EIAM in the brain has not been fully defined yet. This study investigated the molecular signaling nexus of EIAM pathways in the cortex of the brain. C57BL/6 young male mice were randomly assigned to a control group (CON, n = 12) and an endurance exercise group (EXE, n = 12). Our data demonstrated that exercise-induced autophagy coincided with an enhanced anabolic state (p-AKT, p-mTOR, and p-p70S6K); furthermore, mitophagy concurred with enhanced mitochondrial turnover: increases in both fission (DRP1, BNIP3, and PINK1) and fusion (OPA1 and MFN2) proteins. In addition, neither oxidative stress nor sirtuins (SIRT) 1 and 3 were associated with EIAM; instead, the activation of AMPK as well as a JNK-BCL2 axis was linked to EIAM promotion. Collectively, our results demonstrated that EXE-induced anabolic enrichment did not hinder autophagy/mitophagy and that the concurrent augmentation of mitochondrial fusion and fusion process contributed to sustaining mitophagy in the cortex of the brain. Our findings suggest that the EXE-induced concomitant potentiation of the catabolic and anabolic state is a unique molecular mechanism that simultaneously contributes to recycling and rebuilding the cellular structure, leading to upholding healthy cellular environment. Thus, the current study provides a novel autophagy/mitophagy mechanism, from which groundbreaking pharmacological strategies of autophagy can be developed.

Decreased Expression of Sirt1 Contributes to Ocular Behçet's Disease Progression via Th17 and Th22 Response.

BACKGROUND: Previous studies have indicated that Sirtuin 1 (Sirt1) plays an important role in suppressing inflammatory responses in many diseases. However, the Sirt1 levels and role of Sirt1 in ocular Behçet's disease (OBD) have not been fully elucidated. OBJECTIVE: The objective of this study was to investigate the role of Sirt1 in the pathogenesis of OBD. METHODS: Sirt1 and cytokine levels were measured using ELISA. Cell viability was determined using the Cell Counting Kit-8. The frequencies of Th17 and Th22 cells were detected using flow cytometry. RESULTS: We found decreased expression of Sirt1 in CD4+ T cells obtained from patients with active OBD. SRT1720, an agonist of Sirt1, significantly upregulated Sirt1 expression in CD4+ T cells from patients with active OBD. Sirt1 activation by SRT1720 significantly suppressed the production of interleukin (IL)-17 and IL-22 by CD4+ T cells and inhibited the expansion of Th17 and Th22 cells. CONCLUSION: Our results suggest that decreased Sirt1 expression might be involved in the pathogenesis of OBD and that activation of Sirt1 might be considered a potential target for OBD.

Cognitive and Neurochemical Changes Following Polyphenol-Enriched Diet in Rats.

Dietary recommendations are frequently developed based on nutrient deficiency or prevention of disease, but less attention has been paid to the dietary guidelines to promote brain health. Active and healthy aging is a prerequisite for improving quality of life as people age, and evidence is establishing a relationship between diet and brain health. This work studied the effect of a diet based on foods rich in antioxidants, especially polyphenols, in rats, three days a week for 20 months starting at 14 months. Behavioral analysis testing working memory, spatial and episodic memory, as well as brain monoaminergic neurotransmitters involved in these processes but also in general brain health were analyzed. In addition, hippocampal SIRT1 protein which has an important role in regulating normal brain function was evaluated. The results show that long-term intake of polyphenol-enriched diet improves memory and learning, correlating with restoration of brain monoaminergic neurotransmitters and hippocampal SIRT1 levels in aged rats. These results agree with reports revealing a neuroprotective effect of different polyphenolic compounds on age-related brain decline, based on its antioxidant and anti-inflammatory properties; and demonstrate that consumption of antioxidant-rich foods, a few days a week, gives good long-term results in terms of brain health.

Development of activity-based probes for the protein deacylase Sirt1.

Sirtuins are NAD+-dependent protein deacylases that remove acyl modifications from acyl-lysine residues, resulting in essential cellular signaling. Recognized for their role in lifespan extension, humans encode seven sirtuin isoforms (Sirt1-7), and loss of sirtuin deacylase activity is implicated in many aging-related diseases. Despite being intriguing therapeutic targets, cellular studies of sirtuins are hampered by the lack of chemical probes to measure sirtuin activity independent of sirtuin protein levels. Here, we use a modular, peptide-based approach to develop activity-based probes (ABPs) that directly measure Sirt1 activity in vitro and in cell lysates. ABPs were synthesized containing four elements: (1) thioacetyl-lysine for mechanism-based affinity towards only active sirtuins, (2) either histone H3 lysine-14 (H3K14) or p53 sequences for Sirt1 specificity, (3) a diazirine for covalent labeling upon UV irradiation, and (4) an alkyne for bioorthogonal conjugation to a fluorophore for gel-based detection of active Sirt1. Compared to the H3K14 ABP, the p53 ABP showed increased sensitivity and selective labeling of active Sirt1. Acyl-lysine peptide competition, pharmacological inhibition, and inhibitory post-translational modification of Sirt1 resulted in the loss of p53 ABP labeling both in vitro and in HEK293T cell lysates, consistent with the ABP measuring decreased Sirt1 activity. Furthermore, the p53 ABP measured subcellular Sirt1 activity in MCF7 breast cancer cells. The development of a Sirt1-selective ABP that detects Sirt1 activity with an order of magnitude increased sensitivity compared to previous approaches demonstrates the utility of a modular, peptide-based approach for selective-targeting of the sirtuin protein family and provides a framework for further development of sirtuin-selective chemical probes.

Association of sirtuin-1 and vascular endothelial growth factor expression with tumor progression and poor prognosis in liposarcoma.

OBJECTIVES: A relationship exists between sirtuin-1 expression and growth and survival of malignant tumors. This study aimed to investigate the prognostic value of sirtuin-1 and vascular endothelial growth factor (VEGF) expression in patients with liposarcoma by examining associations between their expression levels and clinical outcomes. METHODS: Clinical and histopathological characteristics and follow-up and survival information were retrospectively reviewed for 42 liposarcoma cases. Sirtuin-1 and VEGF protein expression levels were evaluated by immunohistochemistry and their associations with clinical parameters were analyzed using the Spearman-rho test. Univariate and multivariate Cox regression analyses were performed to identify potential prognostic factors. Kaplan-Meier analysis was performed to analyze overall survival. RESULTS: Sirtuin-1 and VEGF protein expression levels were significantly associated with histological grade, metastasis, and American Joint Committee on Cancer stage. A significant positive correlation was observed between sirtuin-1 and VEGF expression levels (R = 0.677). In univariate analysis, sirtuin-1 and VEGF expression were correlated with shorter overall survival, but the association was significant only for sirtuin-1 (hazard ratio = 3.752, 95% confidence interval 1.553-9.062) in multivariate analysis. CONCLUSION: Sirtuin-1 and VEGF expression levels are significantly correlated with progression of liposarcoma, and sirtuin-1 expression significantly predicts a poor prognosis in patients with liposarcoma.

Developmental programming: intrauterine caloric restriction promotes upregulation of mitochondrial sirtuin with mild effects on oxidative parameters in the ovaries and testes of offspring.

According to the developmental origins of health and disease (DOHaD) hypothesis, changes in the maternal environment are known to reprogram the metabolic response of offspring. Known for its redox modulation, caloric restriction extends the lifespan of some species, which contributes to diminished cellular damage. Little is known about the effects of gestational caloric restriction, in terms of antioxidant parameters and molecular mechanisms of action, on the reproductive organs of offspring. This study assessed the effects of moderate (20%) caloric restriction on redox status parameters, molecular expression of sirtuin (SIRT) 1 and SIRT3 and histopathological markers in the ovaries and testes of adult rats that were subjected to gestational caloric restriction. Although enzyme activity was increased, ovaries from female pups contained high levels of oxidants, whereas testes from male pups had decreased antioxidant enzyme defences, as evidenced by diminished glyoxalase I activity and reduced glutathione content. Expression of SIRT3, a deacetylase enzyme related to cellular bioenergetics, was increased in both ovaries and testes. Previous studies have suggested that, in ovaries, diminished antioxidant metabolism can lead to premature ovarian failure. Unfortunately, there is little information regarding the redox profile in the testis. This study is the first to assess the redox network in both ovaries and testes, suggesting that, although intrauterine caloric restriction improves molecular mechanisms, it has a negative effect on the antioxidant network and redox status of reproductive organs of young adult rats.

Genistein protects against acetaminophen-induced liver toxicity through augmentation of SIRT1 with induction of Nrf2 signalling.

Previous studies suggest that genistein protects liver from acetaminophen (APAP)-induced injury, however, the detailed mechanism of the process is still incompletely. Therefore, present study was to investigate the potential mechanism of the genistein mediated protection against APAP-induced hepatotoxicity. As shown, supplementation with 150 mg/kg genistein greatly alleviated the increase in serum alanine aminotransferase (ALT) activity, aspartate aminotransferase (AST) activity, hepatic malondialdehyde (MDA) contents, and reversed the decrease in hepatic GSH levels in response to overdose APAP. At the same time, hepatic SIRT1 protein and activity were markedly upregulated in mouse receiving genistein. However, the amelioration was almost abolished by the knockdown of hepatic SIRT1 expression using lentivirus carrying specific shRNA targeting SIRT1. These results were further validated by histopathology examination. Moreover, depletion of hepatic SIRT1 prevented the accumulation of Nrf2 in nucleus and the upregulation of the antioxidant gene expression in the presence of genistein and/or APAP. Concomitantly, the induced mRNA expression of UDP-glucuronosyltransferases (UGTs) by genistein was largely dependent on the SIRT1 expression and activity. Together, our results support the notion that the strong elevation of SIRT1 expression and activity may represent a potential mechanism of protection against APAP-induced liver injury by genistein.

Reduced SIRT1 and SIRT2 expression promotes adipogenesis of human visceral adipose stem cells and associates with accumulation of visceral fat in human obesity.

BACKGROUND/OBJECTIVES: The histone deacetylases SIRT1 and SIRT2 have been shown to be involved in the differentiation of rodent adipocyte precursors. In light of the differences in gene expression and metabolic function of visceral (V) and subcutaneous (S) adipose tissue (AT) and their resident cells, the aim of this study was to investigate the role of SIRT1 and SIRT2 in the differentiation of adipose stem cells (ASCs) isolated from SAT and VAT biopsies of nondiabetic obese and nonobese individuals. METHODS: Human ASCs were isolated from paired SAT and VAT biopsies obtained from 83 nonobese and 92 obese subjects and were differentiated in vitro. Adipogenesis was evaluated by analyzing the lipid deposition using an image processing software, and gene expression by RT-qPCR. SIRT1 and SIRT2 protein expression was modified by using recombinant adenoviral vectors. RESULTS: Visceral but not subcutaneous ASCs from obese subjects showed an intrinsic increase in both adipogenesis and lipid accumulation when compared with ASCs from nonobese subjects, and this was associated with reduced SIRT1 and SIRT2 mRNA and protein levels. Moreover, adipose tissue mRNA levels of SIRT1 and SIRT2 showed an inverse correlation with BMI in the visceral but not subcutaneous depot. Overexpression of SIRT1 or SIRT2 in visceral ASCs from obese subjects resulted in inhibition of adipocyte differentiation, whereas knockdown of SIRT1 or SIRT2 in visceral ASCs from nonobese subjects enhanced this process. Changes in SIRT1 or SIRT2 expression and adipocyte differentiation were paralleled by corresponding changes in PPARG, CEBPA, and other genes marking terminal adipocyte differentiation. CONCLUSIONS: SIRT1 and SIRT2 modulate the differentiation of human ASC. Reduced expression of SIRT1 and SIRT2 may enhance the differentiation capacity of visceral ASC in human obesity, fostering visceral adipose tissue expansion.

Budesonide and Poractant Alfa prevent bronchopulmonary dysplasia via triggering SIRT1 signaling pathway.

OBJECTIVE: This study aimed to evaluate effect of budesonide combining Poractant Alfa on preventing bronchopulmonary dysplasia (BPD). PATIENTS AND METHODS: A total of 120 preterm infants were involved. pH value, partial pressure of oxygen (PO2), and blood gas analysis were evaluated. Peripheral blood was collected and mononuclear cells were isolated. Reactive oxygen species (ROS) in peripheral blood mononuclear cells (PBMCs) were detected with laser confocal. Sirtuin 1 (SIRT1) in PBMCs was detected using immunofluorescence. SIRT1 and small ubiquitin-like modifier (SUMO)-specific protease 1 (SENP1) were detected with Western blot. RESULTS: Compared with group B, pH value and PO2 were improved significantly in group C and D (p<0.01). Compared with group B, oxygen inhalation duration, rate of having a respirator assisted ventilation, and using pulmonary surfactant (PS) again, and BPD incidence were significantly decreased in other groups (p<0.05). BPD incidence in group D was less than group C (χ2=4.00, p<0.05). Compared with control group, ROS level of neonatal respiratory distress syndrome (NRDS) group was significantly increased, SENP1 was increased, and SIRT1 was decreased in SIRT1 group. Compared with NRDS, when budesonide combined with Poractant Alfa, ROS decreased, SENP1 decreased, SIRT1 nuclear pulp shuttling rate reduced, nuclear SIRT1 increased (p<0.01). Compared with control, ROS level of NRDS group was significantly increased, SENP1 increased, and SIRT1 in nucleus decreased (p<0.05). Compared with NRDS group, when treated with budesonide and Poractant Alfa, ROS levels decreased, SENP1 decreased, nuclear SIRT1 increased (p<0.01). CONCLUSIONS: Budesonide combining Poractant Alfa can prevent BPD in preterm infants by activating the SIRT1 signaling pathway.

ADC correlation with Sirtuin1 to assess early chemoradiotherapy response of locally advanced esophageal carcinoma patients.

AIMS: To determine the biological correlation between apparent diffusion coefficient (ADC) values and Sirtuin1 (SIRT1) levels of tumour tissues in patients with esophageal carcinoma (EC), and to ascertain the treatment biomarker of ADC in predicting the early response of patients undergoing definitive chemoradiotherapy (CRT). METHODS: A total of 66 patients were enrolled, and the specimens of tumour tissues were collected before treatment to perform immunohistochemical (IHC) examinations and quantify the levels of SIRT1. Then all patients were given two esophageal magnetic resonance imaging (MRI) examinations with diffused weighed imaging (DWI) including pretreatment and intra-treatment (1~2 weeks after the start of radiotherapy). The regions of interest (ROIs) were contoured according to the stipulated rules in advance using off-line software, and the values of the ADC in the ROIs were generated automatically. Then, the values of the ADC at baseline and intra-treatment were labeled as pre-ADC and intra-ADC respectively, and ΔADC, ADCratio were calculated. Pearson's correlation coefficients were acquired to estimate the correlation between each of ADC values and SIRT1 levels. Spearman's rank correlation coefficients were acquired to estimate the correlation between early response and the values of each ADC. Receptor operation characteristics (ROC) curves were constructed to estimate the accuracy of the ADC in predicting the early response of CRT. RESULTS: The findings of this study showed different correlations between ADC values and the levels of SIRT1 (ΔADC: r = - 0.943, P = 0.002; ADCratio: r = - 0.911, P = 0.000; intra-ADC: r = - 0.748, P = 0.002; pre-ADC: r = 0.109, P = 0.558). There was a positive correlation between ΔADC and early response to treatment (ρ = 0.615, P = 0.023), and multivariable logistic regression revealed that ΔADC was significantly associated with short-term response of CRT in esophageal carcinoma patients. CONCLUSIONS: In summary, early increases in ADC may facilitate the predication of early CRT response in patients with esophageal squamous cell carcinoma (ESCC), which may be attributed to the different correlation between ADC changes and SIRT1 expression.

Dietary Supplementation of Methyl Donor l-Methionine Alters Epigenetic Modification in Type 2 Diabetes.

SCOPE: The aim of the current study is to evaluate whether l-methionine supplementation (l-Met-S) improves type 2 diabetes-induced alterations in glucose and lipid metabolism by modulating one-carbon metabolism and methylation status. METHODS AND RESULTS: Diabetes is induced in male Sprague-Dawley rats using high-fat diet and low dose streptozotocin. At the end of study, various biochemical parameters, immunoblotting, qRT-PCR and ChIP-qPCR are performed. The first evidence that l-Met-S activates p-AMPK and SIRT1, very similar to "metformin," is provided. l-Met-S improves the altered key one-carbon metabolites in diabetic rats by modulating methionine adenosyl transferase 1A and cystathione ß synthase expression. qRT-PCR shows that l-Met-S alleviates diabetes-induced increase in Forkhead transcription factor 1 expression and thereby regulating genes involved in glucose (G6pc, Pdk4, Pklr) and lipid metabolism (Fasn). Interestingly, l-Met-S inhibits the increased expression of DNMT1 and also prevents methylation of histone H3K36me2 under diabetic condition. ChIP assay shows that persistent increase in abundance of histone H3K36me2 on the promoter region of FOXO1 in diabetic rats and it is recovered by l-Met-S. CONCLUSION: The first evidence that dietary supplementation of l-Met prevents diabetes-induced epigenetic alterations and regulating methionine levels can be therapeutically exploited for the treatment of metabolic diseases is provided.

In silico and in vitro identification of candidate SIRT1 activators from Indonesian medicinal plants compounds database.

Sirtuin 1 (SIRT1) is a class III family of protein histone deacetylases involved in NAD+-dependent deacetylation reactions. It has been suggested that SIRT1 activators may have a protective role against type 2 diabetes, the aging process, and inflammation. This study aimed to explore and identify medicinal plant compounds from Indonesian Herbal Database (HerbalDB) that might potentially become a candidate for SIRT1 activators through a combination of in silico and in vitro methods. Two pharmacophore models were developed using co-crystalized ligands that allosterically bind with SIRT1 similar to the putative ligands used by SIRT1 activators. Then, these were used for the virtual screening of HerbalDB. The identified compounds were subjected to molecular docking and 50 ns molecular dynamics simulation. Molecular dynamics simulation was analyzed using MM-GB(PB)SA methods. The compounds identified by these methods were tested in an in vitro study using a SIRT-Glo™ luminescence assay. Virtual screening using structure-based pharmacophores predicted that mulberrin as the best candidate SIRT1 activator. Virtual screening using ligand-based pharmacophores predicted that gartanin, quinidine, and quinine to be the best candidates as SIRT1 activators. The molecular docking studies showed the important residues involved were Ile223 and Ile227 at the allosteric region. The MM-GB(PB)SA calculations confirmed that mulberrin, gartanin, quinidine, quinine showed activity at allosteric region and their EC50 in vitro values are 2.10; 1.79; 1.71; 1.14 µM, respectively. Based on in silico and in vitro study results, mulberin, gartanin, quinidine, and quinine had good activity as SIRT1 activators.

Age-Related Impairment of Structure and Function of Iliac Artery Endothelium in Rats Is Improved by Elevated Fluid Shear Stress.

BACKGROUND Aging plays an important role in endothelial dysfunction. Fluid shear stress (FSS) can activate endothelial cells (ECs). Herein, we tested the hypothesis that this endothelial impairment could be improved by elevated FSS (EFSS) in aged rats. MATERIAL AND METHODS EFSS was created through ligation of the unilateral common iliac artery in 20-month-old rats, evaluated by measuring blood flow velocity with Doppler spectrum. The effect of FSS on aged ECs was examined by senescence-associated ß-galactosidase (SA-ß-Gal) staining, ultrastructural observation, and immunostaining and qPCR analysis of eNOS and SIRT1 expression on both the mRNA and protein levels. RESULTS (1) FSS was significantly increased in the right common iliac artery (RCIA) in rats with the ligation of the left common iliac artery (LCIA). (2) SA-ß-Gal staining was significantly attenuated by EFSS in the RCIA of aged rats. (3) Ultrastructural observation showed that ECs in the RCIA of normal aged rats became irregular and enlarged, with increasingly polypoid nuclei and fewer mitochondria, whereas ECs in the RCIA of aged rats with LCIA ligation became more prominent and contained more mitochondria. (4) eNOS and SIRT1 expression in the RCIA of aged rats with LCIA ligation was significantly upregulated compared with that in control group rats. CONCLUSIONS The present study for the first time shows that EFSS has the ability to improve age-related impairment of endothelial structure and functions.

Relationship between SIRT1 gene expression level and disease in age-related cataract cases

Background/aim: Age-related cataract is the most important visual impairment all over the world. Epigenetic modifications, especially overexpression of histone deacetylases, have become the focus of interest for cataract development in recent years. Sirtuin 1 (SIRT1), a class II histone deacetylase and a member of the sirtuin family, is one of the best-characterized histone deacetylases and has a pivotal role in age-related diseases. However, the association of SIRT1 with age-related cataracts has not yet been fully elucidated. Therefore, we aimed to determine the expression of SIRT1 in age-related cataract patients. Materials and methods: Expressions of SIRT1 were evaluated by quantitative polymerase chain reaction (qPCR) in patients and healthy controls. RNA samples were collected from the anterior capsule and peripheral blood samples of age-related cataract patients. Human lens epithelial cell line B3 and peripheral blood samples of healthy subjects were used as controls. Results: We determined that the expression of SIRT1 in blood and anterior capsule samples increased significantly compared to the control group (P < 0.05). Conclusion: The expression level of SIRT1 plays a vital role in the development of age-related cataract and it can be used as a biomarker. Thus, SIRT1 inhibitors can be used in the treatment of age-related cataract disease.

Prevention of kidney cell damage in hyperglycaemia condition by adiponectin.

Adiponectin (APN) is an adipocytokine, secreted from adipose tissue and has anti-inflammatory, anti-ageing, and antidiabetic properties. Hyperglycaemia can damage the renal cells, and mammalian target of rapamycin (mTOR), along with Sirtuin 1 (SIRT1), have an important role in kidney cell response to hyperglycaemia. Therefore, understanding the relationship between adiponectin, mTOR, and SIRT1 proteins is beneficial for deciphering the mechanism of adiponectin function. In this study, Human Embryonic Kidney-293 (HEK-293) cells were cultured under normal and high-glucose condition, with and without APN (1, 10, and 100 ng/mL) for 48 hours. mTOR protein expression was evaluated by western blot analysis, and SIRT1 protein was assessed using ELISA method. To evaluate hyperglycaemia-mediated cytotoxicity, cell viability was determined using MTT assay. Data showed that APN in high dose (100 ng/mL) significantly reduced the expression of mTOR and p-mTOR, increased SIRT1 protein, and also improved cell viability compared with the control high glucose (p ≤ 0.05). According to this results, APN can be useful in preventing renal cell damage, by affecting on the expression of mTOR and SIRT1 proteins, as well as increasing the survival of kidney cells in hyperglycaemia conditions. SIGNIFICANCE OF THE STUDY: Adiponectin triggered mTOR/p-mTOR/SIRT1 pathway and decreased cell death in human kidney cells. Our findings provide preliminary experimental data that support further studies on the potential therapeutic role of adiponectin in diabetes and diabetic-induced metabolic complications.

Budesonide, Aclidinium and Formoterol in combination limit inflammaging processes in bronchial epithelial cells exposed to cigarette smoke.

Inflammation and cellular senescence (also called inflammaging) are involved in the pathogenesis of premature lung aging, a key driver of chronic obstructive pulmonary disease (COPD). Downregulation of histone deacetylases and FoxO3 expression, activation of the ERK 1/2 pathway and IL-8 increase are hallmarks of lung inflammaging. The effects of Budesonide (BUD), Aclidinium (ACL) and Formoterol (FO) on lung inflammaging are unknown. This study was aimed to assess the effects of BUD, ACL and FO in bronchial epithelial cells exposed to cigarette smoke extract (CSE) by evaluating: a) Expression of TLR4 and survivin and LPS binding by flow cytometry; b) expression of HDAC2, HDAC3, SIRT1 and FoxO3 and activation of the ERK 1/2 pathway by western blot; c) IL-8 mRNA levels and release by Real Time-PCR and ELISA, respectively. Reported results show that CSE increased TLR4 and survivin, LPS binding, ERK 1/2 activation, IL-8 release and mRNA levels but decreased SIRT1, HDAC2, HDAC3 and FoxO3 nuclear expression. Combined therapy with BUD, ACL and FO counteracted the effects of CSE on LPS binding, FoxO3 nuclear expression, ERK 1/2 activation, survivin and IL-8 release and mRNA levels. These findings suggest a new role of combination therapy with BUD, ACL and FO in counteracting inflammaging processes induced by cigarette smoke exposure.