Role of SIRT1 in regulating endoplasmic reticulum stress in early brain injury after subarachnoid hemorrhage / 国际生物医学工程杂志

Objective:To investigate the effect of Sirtuin 1 (SIRT1) on subarachnoid hemorrhage (SAH) and its possible mechanism.Methods:A mouse model of SAH was constructed by internal carotid artery puncture. The protein and mRNA expression levels of SIRT1 at 0, 3, 6, 12, 24, 48, and 72 h were detected by Western Blot and qRT-PCR. A Western Blot assay was used to examine SIRT1 and the expression levels of endoplasmic reticulum stress-related markers GRP78, p-PERK/PERK, p-eIF2α/eIF2α, and CHOP after administration of a SIRT1 inhibitor or SIRT1 si-RNA. At 24 h after SAH, subarachnoid hemorrhage volume, neurological function score, brain water content, and blood-brain barrier integrity were measured.Results:The highest expression of SIRT1 protein and mRNA was observed at 24 h compared with other time points, and the differences were statistically significant (all P < 0.001). Inhibition of SIRT1 expression leads to increased expression of endoplasmic reticulum stress-related proteins GRP78, p-PERK/PERK, p-eIF2α/eIF2α, and CHOP, exacerbating hemorrhage and brain water content, disrupting blood-brain barrier integrity, and significantly reducing neurological function scores. Conclusions:Inhibition of SIRT1 expression significantly increased the endoplasmic reticulum response to excitation and exacerbated early brain injury after SAH.

Pre-treatment of the beta3-adrenergic receptor agonist BRL37344 reduces in vivo myocardial ischemia/reperfusion injury by improving AMPK and SIRT1 activity and by suppressing mTOR and p70S6K signaling pathways

Abstract This study aimed to investigate the role and signaling pathways of β3-AR in myocardial ischemia/reperfusion (I/R) injury, which is one of the leading causes of death worldwide. 47 male rats were randomly divided into two main groups to evaluate infarct size and molecular parameters. Rats in both groups were randomly divided into 4 groups. Control (sham), I/R (30 min ischemia/120 min reperfusion), BRL37344 (BRL) (A) (5 µg/kg single-dose pre-treatment (preT) before I/R) and BRL (B) (5 µg/kg/day preT for 10 days before I/R). Infarct size was determined with triphenyltetrazolium chloride staining and analyzed with ImageJ program. The levels of AMPK, SIRT1, mTOR, and p70SK6 responsible for cellular energy and autophagy were evaluated by western blot. Infarct size increased in the I/R group (44.84 ± 1.47%) and reduced in the single-dose and 10-day BRL-treated groups (32.22 ± 1.57%, 29.65 ± 0.55%; respectively). AMPK and SIRT1 levels were decreased by I/R but improved in the treatment groups. While mTOR and p70S6K levels increased in the I/R group, they decreased with BRL preT. BRL preT protects the heart against I/R injury. These beneficial effects are mediated in part by activation of AMPK and SIRT1, inhibition of mTOR and p70S6K, and consequently protected autophagy.

Study on differential expression of Sirtuin1 in type A aortic dissection pateints at diverse ages / 中国胸心血管外科临床杂志

@#Objective    To explore the differential expression of Sirtuin1 (SIRT1) in type A aortic dissection at diverse ages. Methods    The expression of SIRT1 and monocyte chemoattractant protein-1 (MCP-1) in aortic tissue of the patients with type A aortic dissection (an aortic dissection group) and coronary heart disease (a control group) from 2019 to 2020 in the First Hospital of China Medical University was analyzed. In each group, the patients were divided into 3 subgroups according to the age (a younger subgroup, <45 years; a middle age subgroup, 45-60 years; an elderly subgroup, > Compared with the control group, SIRT1 protein expression decreased significantly in the aortic dissection group (the younger group: 0.64±0.18 vs. 1.18±0.47; the middle age group: 0.43±0.26 vs. 0.69±0.32; the elderly group: 0.31±0.24 vs. 0.45±0.29, P<0.01). The Western blotting results showed that the expression of SIRT1 protein in the aortic dissection group decreased with age (P<0.01). The MCP-1 protein expression of younger and middle age patients in the aortic dissection group was increased compared with that in the control group (the younger group: 0.65±0.27 vs. 0.38±0.22; the middle age group: 1.08±0.30 vs. 0.46±0.36, P<0.001). MCP-1 expression increased with age (P<0.01). The result of immunohistochemical staining for SIRT1 protein was similar to that of Western blotting. Conclusion    The expression of SIRT1 decreases in patients with aortic dissection disease, and declines with age. SIRT1 may play an important role in the treatment and screening of type A aortic dissection.60 years). The quantitative real-time PCR, Western blotting and immunochemical stainning were used to detect the mRNA or protein expression of SIRT1 and MCP-1. Results    A total of 60 patients were included in each group, including 79 males and 41 females. There were 20 patients in the yonger, middle age and elderly subgroups for the two groups, respectively. Compared with the control group, the expression of SIRT1 mRNA decreased in the aortic dissection group (the younger subgroup: 4.54±1.52 vs. 8.78±2.57; the middle age group: 2.70±1.50 vs. 5.74±1.07; the elderly group: 1.41±1.33 vs. 3.09±1.14, P<0.001). Meanwhile, SIRT1 mRNA in the aortic dissection group declined with age (P<0.01).

Role of SIRT1/NLRP3 signaling pathway in sevoflurane postconditioning-induced attenuation of oxygen-glucose deprivation and restoration injury in HT22 cells / 中华麻醉学杂志

Objective:To evaluate the role of silent information regulator-1 (SIRT1)/nucleotide-binding domain (NOD)-like receptor protein-3 (NLRP3) signaling pathway in sevoflurane postconditioning-induced attenuation of oxygen-glucose deprivation and restoration (OGD/R) injury in mouse hippocampal neuronal cell line (HT22) cells.Methods:The HT22 cells were seeded in a culture plate (96-well plate, 100 μl/well; 6-well plate, 2 ml/well) at the density of 5×10 4 cells/ml or in a culture dish (6 cm in diameter) and then divided into 4 groups ( n=24 each) using a random number table method: control group (Control group), OGD/R group, sevoflurane postconditioning group (SPC group), and SIRT1 small interfering RNA group (si-SIRT 1 group). In Control group, cells were cultured at 37 ℃ in normal culture atmosphere. In OGD/R group, the culture medium was replaced with glucose-free serum-free culture medium, and cells were exposed to 95% N 2+ 5% CO 2 for 4 h in an incubator at 37 ℃, and then the glucose-free serum-free culture medium was replaced with the primary culture medium, and cells were cultured for 24 h at 37 ℃ in normal culture atmosphere. In SPC group, the glucose-free serum-free culture medium was replaced with the primary cell culture medium after 4-h oxygen and glucose deprivation, the cells were put into the hypoxia incubator chamber which was filled with 2% sevoflurane immediately after start of reoxygenation, then the chamber was placed in an incubator and the cells were cultured for 1 h at 37 ℃ in normal culture atmosphere, and finally the cells were removed from the chamber and cultured for 23 h at 37 ℃ in normal culture atmosphere. In si-SIRT1 group, SIRT1 small interfering RNA 150 pmol was added at 24 h before surgery, cells were then incubated, and the other procedures were the same as those previously described in group SPC. The cell survival rate was determined using MTT assay. TUNEL assay was used to detect cell apoptosis, and the apoptosis rate was calculated. The expression of SIRT1, NLRP3, IL-1β and IL-18 mRNA was determined using polymerase chain reaction. The expression of SIRT1, NLRP3, interleukin-1beta (IL-1β) and IL-18 was detected using Western blot. Results:Compared with Control group, the cell survival rate was significantly decreased, the apoptosis rate was increased, the expression of SIRT1 protein and mRNA was down-regulated, and the expression of NLRP3, IL-1β and IL-18 protein and mRNA was up-regulated in OGD/R group ( P<0.05). Compared with OGD/R group, the cell survival rate was significantly increased, the apoptosis rate was decreased, the expression of SIRT1 protein and mRNA was up-regulated, and the expression of NLRP3, IL-1β and IL-18 protein and mRNA was down-regulated in SPC group ( P<0.05). Compared with SPC group, the cell survival rate was significantly decreased, the apoptosis rate was increased, the expression of SIRT1 protein and mRNA was down-regulated, and the expression of NLRP3, IL-1β and IL-18 protein and mRNA was up-regulated in si-SIRT1 group ( P<0.05). Conclusions:Activation of SIRT1-NLRP3 signaling pathway is involved in sevoflurane postconditioning-induced attenuation of OGD/R injury in HT22 cells.

Relationship between SIRT1 and ferroptosis during curcumin-induced reduction of acute lung injury in a mouse model of sepsis / 中华麻醉学杂志

Objective:To evaluate the relationship between silent information regulator 1 (SIRT1) and ferroptosis during curcumin-induced reduction of acute lung injury in a mouse model of sepsis.Methods:One hundred and fifty-two SPF-grade male C57BL/6J mice, aged 8 weeks, weighing 23-27 g, were divided into 4 groups ( n=38 each) using a random number table method: sham operation group (C group), sepsis group (S group), curcumin group (Cur group) and curcumin plus SIRT1 inhibitor EX527 group (CE group). Curcumin 200 mg/kg was administered by intragastric gavage every day in Cur group. Curcumin 200 mg/kg was administered by intragastric gavage every day and EX527 5 mg/kg was intraperitoneally injected in CE group. The equal volume of solvent dimethyl sulfoxide (DMSO) was given in C group and S group. Sepsis model was developed by cecal ligation and puncture (CLP) after 5 days of consecutive administration in anesthetized animals. Twenty mice in each group were randomly selected to observe the survival condition within 7 days after CLP. The bronchoalveolar lavage fluid (BALF) was collected at 24 h after developing the model to determine the concentrations of tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β), IL-6 and IL-18 (by enzyme-linked immunosorbent assay), and the lung tissues were obtained for microscopic examination of the pathological changes which were scored and for determination of wet-to-dry lung weight (W/D) ratio, contents of glutathione (GSH), malondialdehyde (MDA) and iron (by colorimetry), and expression of SIRT1, glutathione peroxidase 4 (GPX4) and Acyl-CoA synthetase long chain family member 4 (ACSL4) (by Western blot). Results:Compared with C group, the 7-day survival rate after CLP was significantly decreased, the concentrations of TNF-α, IL-1β, IL-6 and IL-18 in BALF, W/D ratio and lung injury score were increased, the content of GSH in lung tissues was decreased, the contents of MDA and iron were increased, the expression of SIRT1 and GPX4 was down-regulated, and the expression of ACSL4 was up-regulated in S group ( P<0.05). Compared with S group, the 7-day survival rate after CLP was significantly increased, the concentrations of TNF-α, IL-1β, IL-6 and IL-18 in BALF, W/D ratio and lung injury score were decreased, the content of GSH was increased, the contents of MDA and iron were decreased, the expression of SIRT1 and GPX4 was up-regulated, and the expression of ACSL4 was down-regulated in Cur group ( P<0.05). Compared with Cur group, the 7-day survival rate after CLP was significantly decreased, the concentrations of TNF-α, IL-1β, IL-6 and IL-18 in BALF, W/D ratio and lung injury score were increased, the content of GSH was decreased, the contents of MDA and iron were increased, the expression of SIRT1 and GPX4 was down-regulated, and the expression of ACSL4 was up-regulated in CE group ( P<0.05). Conclusions:The mechanism by which curcumin attenuates acute lung injury may be related to activation of SIRT1 and further inhibition of ferroptosis in mice.

Relationship between miR-27a and SIRT1 during myocardial ischemia-reperfusion in rats / 中华麻醉学杂志

Objective:To evaluate the relationship between microRNA-27a (miR-27a) and silent information regulator 1 (SIRT1) during myocardial ischemia-reperfusion (I/R) in rats.Methods:Fifty clean-grade healthy male Sprague-Dawley rats, aged 2-3 months, weighing 220-280 g, were divided into 5 groups ( n=10 each) by the random number table method: sham operation group (Sham group), myocardial I/R group (I/R group), AAV9-miR-27a overexpression + myocardial I/R group (AAV+ I/R group), miR-27a antagomir + myocardial I/R group (AG+ I/R group) and AAV9-miR-27a negative control+ myocardial I/R group (NC+ I/R group). The myocardial I/R injury model was prepared by ligating the anterior descending branch of the left coronary artery for 30 min followed by 120 min reperfusion. At day 14 before ischemia, AAV9-miRNA-27a adeno-associated virus 2×10 11 v. g was injected via the tail vein in AAV+ I/R group, and AAV9-miR-27a NC 2×10 11 v. g was injected via the tail vein in NC+ I/R group. miR-27a antagomir 10 mg/kg was injected via the tail vein once a day at 3 days before ischemia in AG+ I/R group. At the end of 120 min of reperfusion, serum cardiac troponin T(cTnT), creatine kinase isoenzymes (CK-MB) and lactic dehydrogenase (LDH) concentrations and contents of glutathione (GSH), superoxide dismutase (SOD) and malondialdehyde (MDA) in myocardial tissues were determined by enzyme-linked immunosorbent assay, the percentage of myocardial infarct volume by TTC staining, the expression of miR-27a in myocardial tissues by quantitative real-time polymerase chain reaction, and the expression of SIRT1 in myocardial tissues by Western blot. Results:Compared with Sham group, the percentage of myocardial infarct volume and serum concentrations of cTnT, CK-MB and LDH were significantly increased, the contents of GSH and SOD in myocardial tissues were decreased, MDA contents were increased, miR-27a expression was up-regulated, and SIRT1 expression was down-regulated in I/R group ( P<0.05). Compared with I/R group, the percentage of myocardial infarct volume and serum concentrations of cTnT, CK-MB and LDH were significantly increased, the contents of GSH and SOD in myocardial tissues were decreased, MDA contents were increased, miR-27a expression was up-regulated, and SIRT1 expression was down-regulated in AAV+ I/R, and the percentage of myocardial infarct volume and serum concentrations of cTnT, CK-MB and LDH were significantly decreased, the contents of GSH and SOD in myocardial tissues were increased, MDA contents were decreased, miR-27a expression was down-regulated, and SIRT1 expression was up-regulated in AG+ I/R group ( P<0.05), and no significant change was found in the parameters mentioned above in NC+ I/R group ( P>0.05). Compared with AAV+ I/R group, the percentage of myocardial infarct volume and serum concentrations of cTnT, CK-MB and LDH were significantly decreased, the contents of GSH and SOD in myocardial tissues were increased, MDA contents were decreased, miR-27a expression was down-regulated, and SIRT1 expression was up-regulated in AG+ I/R group ( P<0.05). Conclusions:miR-27a is involved in the pathophysiological mechanism underlying myocardial I/R injury probably through inhibition of SIRT1 expression in rats.

Effect of exosomes derived from bone mesenchymal stem cells on postoperative cognitive function and SIRT1/NF-κB signaling pathway in aged mice / 中华麻醉学杂志

Objective:To evaluate the effect of exosomes derived from bone mesenchymal stem cells (BMSCs-EXO) on the postoperative cognitive function and silent infomation regulator 1 (SIRT1)/ nuclear factor kappa B (NF-κB) signaling pathway in aged mice.Methods:BMSCs-EXO were isolated by differential centrifugation method and then identified. Twenty healthy male C57BL/6 aged mice, aged 18 months, weighing 35-40 g, were divided into 4 groups ( n=5 each) using a random number table method: sham operation group (Sham group), operation group (O group), BMSCs-EXO group and EX527 (SIRT1 inhibitor)group. The abdomen regions were shaved for sterilization without exploratory laparotomy in Sham group. Exploratory laparotomy was performed in O group. BMSCs-EXO 50 μg was injected through the tail vein at 1 h before surgery in BMSCs-EXO group. EX527 5 mg/kg was intraperitoneally injected daily at 1-3 days before surgery, and BMSCs-EXO 50 μg was injected through the tail vein at 1 h before surgery in EX527 group. Morris water maze test was used to evaluate the learning and memory ability for 5 consecutive days staring from the 1st day after surgery. Mice were sacrificed at 1 h after the end of Morris water maze test on day 5 after surgery, and the hippocampal tissues were collected for observation of the pathological changes of hippocampal CA1 region and for determination of the expression of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and IL-1β mRNA (quantitative real-time polymerase chain reaction) and SIRT1 and NF-κB p65 (by Western blot). Results:Compared with Sham group, the escape latency was significantly prolonged, the times of original platform crossing were decreased, the swimming time spent in the original platform quadrant was shortened, the expression of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and IL-1β mRNA was up-regulated, the SIRT1 expression was down-regulated, the NF-κB p65 expression was up-regulated ( P<0.05), and the pathological changes of hippocampal tissues in CA1 region were found in O group. Compared with O group, the escape latency was significantly shortened, the times of original platform crossing were increased, the swimming time spent in the original platform quadrant was prolonged, the expression of TNF-α, IL-6 and IL-1β mRNA was down-regulated, the expression of SIRT1 was up-regulated, the expression of NF-κB p65 was down-regulated ( P<0.05), and the pathological changes of hippocampal tissues in CA1 region were significantly attenuated in BMSCs-EXO group ( P<0.05). Compared with BMSCs-EXO group, the escape latency was significantly prolonged, the times of original platform crossing were decreased, the swimming time spent in the original platform quadrant was shortened, the expression of TNF-α, IL-6 and IL-1β mRNA was up-regulated, the SIRT1 expression was down-regulated, the NF-κB p65 expression was up-regulated ( P<0.05), and the pathological changes of hippocampal tissues in CA1 region were accentuated in EX527 group. Conclusions:BMSCs-EXO can improve the postoperative cognitive function in aged mice, and the mechanism may be associated with the activation of SIRT1/NF-κB signaling pathway.

Role of SIRT1 in mitochondrial dysfunction in mice with lipopolysaccharide-induced brain injury / 中华麻醉学杂志

Objective:To evaluate the role of silent information regulator sirtuin 1 (SIRT1) in mitochondrial dysfunction in mice with lipopolysaccharide (LPS)-induced brain injury.Methods:Eighty clean-grade male C57BL/6 mice, aged 6-8 weeks, were divided into 4 groups ( n=20 each) by the random number table method: control group (group C), LPS-induced brain injury group (LPS group), LPS-induced brain injury plus SIRT1 inhibitor EX527 group (LPS+ E group), and LPS-induced brain injury plus SIRT1 agonist SRT1720 group (LPS+ S group). Brain injury was induced by intravenous injection of LPS 10 mg/kg. EX527 10 mg/kg was intraperitoneally injected at 72 h before LPS injection in group LPS+ E, and the equal volume of dimethyl sulfoxide was intraperitoneally injected instead in the other three groups. SRT1720 100 mg/kg was intraperitoneally injected at 30 min before LPS injection in group LPS+ S, and the equal volume of dimethyl sulfoxide was intraperitoneally injected instead in the other three groups. The novel object recognition test was performed at 24 h after LPS injection, then the mice were sacrificed, and hippocampal tissues were harvested for determination of the number of the normal neurons in the hippocampal CA1 area, ATP content and activities of mitochondrial respiratory chain complexes Ⅰ, Ⅱ, Ⅲ and Ⅳ (by spectrophotometry), and mitochondrial membrane potential (MMP) (by Jc-1 staining) and for microscopic examination of pathological changes (by Nissl staining) and ultrastructure of neuronal mitochondria (with a transmission electron microscope). Results:Compared with group C, the preference index in novel object recognition, normal neuron count, activities of mitochondrial respiratory chain complexes Ⅰ, Ⅱ, Ⅲ and Ⅳ, MMP and ATP content were significantly decreased ( P<0.05), damage to hippocampal neurons was found, mitochondrial swelling was observed and cristae structure ruptured in LPS, LPS+ S and LPS+ E groups. Compared with group LPS, the preference index in novel object recognition, activities of mitochondrial respiratory chain complexes, MMP and ATP content were significantly decreased ( P<0.05), neuronal damage was aggravated, the mitochondrial swelling and fracture of crista structure were accentuated in group LPS+ E; the preference index in novel object recognition, activities of mitochondrial respiratory chain complexes, MMP and ATP content were significantly increased ( P<0.05), neuronal damage was alleviated, and the mitochondrial swelling and fracture of crista structure were ameliorated in group LPS+ S. Conclusions:Activation of SIRT1 can improve mitochondrial dysfunction and alleviate LPS-induced brain injury in mice.

Role of SIRT1/NF-κB signaling pathway in mild hypothermia-induced promotion of microglial polarization during oxygen-glucose deprivation and restoration / 中华麻醉学杂志

Objective:To evaluate the role of Sirtuin 1/nuclear factor κB (SIRT1/NF-κB) signaling pathway in mild hypothermia-induced promotion of microglial polarization during oxygen-glucose deprivation and restoration (OGD/R).Methods:The well-grown BV2 microglia were divided into 4 groups ( n=36 each) using the random number table method: control group (group C), OGD/R group (group O), mild hypothermia group (group M), and mild hypothermia+ SIRT1 specific inhibitor EX527 group (group ME). Cells in group C were commonly cultured without any treatment. Cells in group O were subjected to 3 h of OGD followed by 21 h of restoration of O 2-glucose supply at 37 ℃. Cells in group M were subjected to 3 h of OGD followed by 21 h of restoration of O 2-glucose supply at 33 ℃. Cells in group ME were co-cultured with inhibitor EX527 (final concentration 5 nmol/L) for 12 h in the medium before OGD/R, and the other procedures were conducted as previously described in group M. The cell survival rate was detected by CCK-8 assay. The levels of tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β) and interleukin-10 (IL-10) in supernatant were detected by enzyme-linked immunosorbent assay. The expression of CD206, CD32, inducible nitric oxide synthase (iNOS) and arginine synthase 1 (Arg-1) mRNA was detected by quantitative real-time polymerase chain reaction. The expression of CD206 and CD32 was detected by immunofluorescent staining. The expression of iNOS, Arg-1, SIRT1, NF-κB p65 (p65) and acetylated NF-κB (Ac-p65) was detected by Western blot. Results:Compared with group C, the cell survival rate was significantly decreased, the concentrations of TNF-α, IL-6 and IL-10 in the supernatant were increased, the expression of CD206, Arg-1, CD32 and iNOS was up-regulated, the expression of SIRT1 was down-regulated, and the Ac-p65/p65 ratio was increased in group O ( P<0.05). Compared with group O, the cell survival rate was significantly increased, the concentrations of TNF-α and IL-6 in the supernatant were decreased, the concentration of IL-10 was increased, the expression of CD206, Arg-1 and SIRT1 was up-regulated, the expression of CD32 and iNOS was down-regulated, and the Ac-p65/p65 ratio was decreased in group M ( P<0.05). Compared with group M, the cell survival rate was significantly decreased, the concentrations of TNF-α and IL-6 in the supernatant were increased, the concentration of IL-10 was decreased, the expression of CD206, Arg-1 and SIRT1 was down-regulated, the expression of CD32 and iNOS was up-regulated, and the Ac-p65/p65 ratio was increased in group ME ( P<0.05). Conclusions:SIRT1/NF-κB signaling pathway is involved in mild hypothermia-induced promotion of microglial polarization during OGD/R.

Role of SIRT1 and associated microRNAs in dexmedetomidine-induced alleviation of renal injury in diabetic mice / 中华麻醉学杂志

Objective:To evaluate the role of silencing regulatory protein (SIRT1) and its associated microRNAs (miRNAs) in dexmedetomidine-induced attenuation of renal damage in diabetic mice.Methods:SPF grade C57 male mice, aged 8 weeks, in which diabetes mellitus model was developed by intraperitoneal injection of 1% streptozotocin, were used.Thirty mice in which the model was successfully developed were divided into 5 groups ( n=6 each) using the random number table method: diabetes mellitus group (D group), diabetes mellitus + dexmedetomidine group (DD group), diabetes mellitus + dexmedetomidine + EX527 group (DDE group), diabetes mellitus + dexmedetomidine + miR-34a-3p-agomir group (DDH group), and diabetes mellitus + dexmedetomidine + miR-34a-3p-agomirNC group (DDC group). Six normal mice were selected as control group (C group). Dexmedetomidine 40 μg/kg was intraperitoneally injected once every 2 h, 3 times in total in DD, DDE, DDH and DDC groups.miR-34a-3p-agomir and miR-34a-3p-agomirNC 2.5 mmol were intraperitoneally injected via the tail vein at 72 h before dexmedetomidine administration once every 3 days, 2 times in total in DDH and DDC groups, respectively.SIRT1 inhibitor EX527 10 mg/kg was intraperitoneally injected at 1 h before dexmedetomidine administration in group DDE.At 24 h after the end of administration, serum concentrations of IL-6, IL-18, Cr and BUN, contents of nitric oxide (NO) and total antioxidant capacity (T-AOC), ROS activity, and expression of SIRT1, FoxO3a and P53 protein and mRNA, and expression of miR-217, miR-138 and miR-34a in renal tissues were determined. Results:Compared with group C, the serum IL-6, IL-18, Cr and BUN concentrations, contents of T-AOC and NO, and ROS activity were significantly increased, the expression of P53 protein and mRNA, miR-34a, miR-217 and miR-138 was up-regulated, and the expression of SIRT1 and FoxO3a protein and mRNA was down-regulated in group D ( P<0.05). Compared with group D, serum IL-6, IL-18, Cr and BUN concentrations, ROS activity and NO content were significantly decreased, T-AOC content was increased, the expression of SIRT1 and FoxO3a protein and mRNA was up-regulated, and the expression of miR-34a was down-regulated in group DD ( P<0.05). Compared with group DD, the serum IL-6, IL-18, Cr and BUN concentrations, NO content and ROS activity were significantly increased, T-AOC content was decreased, and the expression of SIRT1 and FoxO3a protein and mRNA was down-regulated in group DDE and group DDH ( P<0.05), no significant change was found in the expression of P53 protein and mRNA, miR-217, miR-34a and miR-138 in group DDE ( P>0.05), and the expression of P53 protein and mRNA and miR-34a was significantly up-regulated in group DDH ( P<0.05). Conclusions:The mechanism by which dexmedetomidine attenuates renal injury may be related to down-regulation of miR-34a expression, which further up-regulates SIRT1/FoxO3 expression and decreases oxidative stress in diabetic mice.

Clinical significance of sirtuin 1 level in sepsis: correlation with disease risk, severity, and mortality risk

This study aimed to investigate the value of sirtuin 1 (SIRT1) in differentiating sepsis patients from healthy controls (HCs), and its correlation with inflammation, disease severity, as well as prognosis in sepsis patients. Serum samples were collected from 180 sepsis patients and 180 age- and gender-matched HCs. The SIRT1 level in the serum samples was detected by enzyme-linked immunoassay. The clinical data of the sepsis patients were documented, and their disease severity scores and 28-day mortality rate were assessed. SIRT1 was decreased in sepsis patients compared with HCs, and the receiver operating characteristic curve (ROC) showed that SIRT1 distinguished sepsis patients from HCs (area under the curve (AUC): 0.901; 95% confidence interval (CI): 0.868-0.934). In sepsis patients, SIRT1 negatively correlated with serum creatinine (Scr), white blood cells (WBC), C-reactive protein (CRP), acute physiology, and chronic health evaluation II (APACHE II) score, and sequential organ failure assessment (SOFA) score, while it positively correlated with albumin. No correlation of SIRT1 with primary infection site or primary organism was observed. Furthermore, SIRT1 was reduced in 28-day non-survivors compared with 28-day survivors, and subsequent ROC showed that SIRT1 predicted 28-day mortality of sepsis patients (AUC: 0.725; 95% CI: 0.651-0.800), and its prognostic value was not inferior to Scr, albumin, WBC, and CRP, but was less than SOFA score and APACHE II score. In conclusion, measurement of serum SIRT1 might assist with the optimization of disease assessment, management strategies, and survival surveillance in sepsis patients.

Restricted feeding modulates peripheral clocks and nutrient sensing pathways in rats

ABSTRACT Objective: Feeding restriction in rats alters the oscillators in suprachiasmatic, paraventricular, and arcuate nuclei, hypothalamic areas involved in food intake. In the present study, using the same animals and experimental protocol, we aimed to analyze if food restriction could reset clock genes ( Clock, Bmal1 ) and genes involved in lipid metabolism ( Pgc1a, Pparg, Ucp2 ) through nutrient-sensing pathways ( Sirt1, Ampk, Nampt ) in peripheral tissues. Materials and methods: Rats were grouped according to food access: Control group (CG, food ad libitum ), Restricted night-fed (RF-n, food access during 2 h at night), Restricted day-fed (RF-d, food access during 2 h in the daytime), and Day-fed (DF, food access during 12 h in the daytime). After 21 days, rats were decapitated at ZT3 (0900-1000 h), ZT11 (1700-1800 h), or ZT17 (2300-2400 h). Blood, liver, brown (BAT) and peri-epididymal (PAT) adipose tissues were collected. Plasma corticosterone and gene expression were evaluated by radioimmunoassay and qPCR, respectively. Results: In the liver, the expression pattern of Clock and Bmal1 shifted when food access was dissociated from rat nocturnal activity; this phenomenon was attenuated in adipose tissues. Daytime feeding also inverted the profile of energy-sensing and lipid metabolism-related genes in the liver, whereas calorie restriction induced a pre-feeding increased expression of these genes. In adipose tissues, Sirt1 expression was modified by daytime feeding and calorie restriction, with concomitant expression of Pgc1a , Pparg , and Ucp2 but not Ampk and Nampt . Conclusion: Feeding restriction reset clock genes and genes involved in lipid metabolism through nutrient-sensing-related genes in rat liver, brown, and peri-epididymal adipose tissues.

Role of NAD +-mediated deacetylation activity of SIRT1 in endotoxin-induced acute lung injury in mice / 中华麻醉学杂志

Objective:To evaluate the role of nicotinamide adenine dinucleotide (NAD + )-mediated deacetylation activity of silent information regulator 1 (SIRT1) in endotoxin-induced acute lung injury (ALI) in mice. Methods:Twenty-five SPF clean-grade healthy male C57BL/6 mice including 10 wild-type (WT) and 15 NMNAT1 conditional-knockout (KO) mice, aged 6-8 weeks, weighing 20-25 g, were selected.The WT mice were divided into 2 groups ( n=5 each) using a random number table method: control group (group WT+ C) and ALI group (group WT+ ALI). The KO mice were divided into 3 groups ( n=5 each) using a random number table method: control group (group KO+ C), ALI group (group KO+ ALI) and ALI plus NAD + precursor substances nicotinamide mononucleotide (NMN) group (KO+ LPS+ NMN group). ALI was produced with lipopolysaccharide (LPS) 15 mg/kg injected intravenously.NMN 500 mg/kg was intraperitoneally injected at 1 h before injection of LPS in KO+ ALI+ NMN group, while the equal volume of normal saline was given instead in control group.Blood samples were collected from the abdominal aorta at 12 h after LPS or normal saline injection for blood gas analysis, and the animals were then sacrificed and the lung tissues were removed for microscopic examination of pathologic changes which were scored and for determination of wet/dry weight ratio (W/D ratio), and interleukin-6 (IL-6), IL-1β and tumor necrosis factor-alpha (TNF-α) contents (by enzyme-linked immunosorbent assay)and content of NAD + (using a spectrophotometer) and levels of SIRT1, acetylated nuclear factor kappaB (Ac-NF-κB), acetylated p53 (Ac-p53), acetylated FoxO1 (Ac-FoxO1) and acetylated PGC1α (Ac-PGC1α) (by Western blot). Results:Compared with group C, pH value and PaO 2 were significantly decreased, the PaCO 2, W/D ratio, lung injury score, contents of IL-6, IL-1β, TNF-α and NAD + were increased, expression of SIRT1 was up-regulated, and expression of Ac-NF-κB, Ac-p53, Ac-FoxO1 and Ac-PGC1α was down-regulated in group ALI ( P<0.05). Compared with group WT+ ALI, pH value and PaO 2 were significantly decreased, the PaCO 2, W/D ratio, lung injury score, contents of IL-6, IL-1β and TNF-α were increased, NAD + content was decreased, expression of SIRT1 was down-regulated, and expression of Ac-NF-κB, Ac-p53, Ac-FoxO1 and Ac-PGC1α was up-regulated in group KO+ ALI ( P<0.05). Compared with group KO+ ALI, pH value and PaO 2 were significantly increased, the PaCO 2, W/D ratio, lung injury score, contents of IL-6, IL-1β and TNF-α were decreased, NAD + content was increased, expression of SIRT1 was up-regulated, and expression of Ac-NF-κB, Ac-p53, Ac-FoxO1 and Ac-PGC1α was down-regulated in group KO+ ALI+ NMN ( P<0.05). Conclusion:The enhanced NAD + -mediated deacetylation activity of SIRT1 is involved in the endogenous protective mechanism in mice with endotoxin-induced ALI.

Relationship between SIRT1 and STAT3 acetylation during high glucose-induced cardiac microvascular endothelial cell injury / 中华麻醉学杂志

Objective:To evaluate the relationship between silence information regulator 1 (SIRT1) and signal transducers and activators of transcription 3 (STAT3) acetylation during high glucose-induced cardiac microvascular endothelial cell injury.Methods:Cardiac microvascular endothelial cells of Sprague-Dawley rats were cultured.The cells at the logarithmic growth phase were selected and divided into 3 groups ( n=24 each) using a random number table method: control group (C group), high glucose group (HG group) and high glucose+ SIRT1 agonist SRT1720 group (HG+ SRT group). The cardiac microvascular endothelial cells were seeded in a 6- or 96-well cell culture plate at a density of 2×10 5 cells/ml.When the cell density reached 50%, the culture medium was then replaced with high-glucose (glucose 33 mmol/L) DMEM culture medium containing with 10% fetal bovine serum and 1% double antibody in HG and HG+ SRT groups.In group HG+ SRT, 20 μmol/L SRT1720 was added simultaneously, and the cells were cultured at 37 ℃ in an incubator with 5% CO 2 for 24 h. The cell viability was determined by CCK-8 assay, the activity of superoxide dismutase (SOD) was detected using a spectrophotometer, the levels of lactic dehydrogenase (LDH), interleukin-6 (IL-6) and tumor necrosis factor-β (TNF-β) in the supernatant were detected by enzyme-linked immunosorbent assay, and the expression of SIRT1, acetylated STAT3 (ac-STAT3) and phosphorylated STAT3 (p-STAT3) was determined by Western blot. Results:Compared with C group, the cell viability and SOD activity were significantly decreased, levels of LDH, IL-6 and TNF-β in the supernatant were increased, expression of SIRT1 was down-regulated, and expression of ac-STAT3 and p-STAT3 was up-regulated in group HG and group HG+ SRT ( P<0.05). Compared with group HG, the cell viability and SOD activity were significantly increased, levels of LDH, IL-6 and TNF-β in the supernatant were decreased, expression of SIRT1 was up-regulated, and expression of ac-STAT3 and p-STAT3 was down-regulated in group HG+ SRT ( P<0.05). Conclusion:SIRT1 can alleviate high glucose-induced cardiac microvascular endothelial cell injury by promoting STAT3 deacetylation.

Effects of oleanolic acid on early brain injury after subarachnoid hemorrhage through SIRT1 / 国际生物医学工程杂志

Objective:To investigate the effect of oleanolic acid (OA) on Sirtuin1 (SIRT1)-mediated high-mobility group box 1(HMGB1) deacetylation in the early brain injury after subarachnoid hemorrhage (SAH).Methods:A total of 176 male Sprague-Dawley rats were randomly divided into Sham operation (Sham group) ( n=48), SAH group ( n=48), OA group ( n=48) and Sirtinol group ( n=32). Rats in the SAH group, OA group and the Sirtinol group all adopted internal carotid artery puncture to construct SAH model, while rats in the sham group did not adopt puncture. One hour after modeling, the rats in the OA group were given intraperitoneal injection of OA (20 mg/kg), and the rats in the Sirtinol group were given intracerebroventricular injection of Sirtinol (2 mmol/L, 30 μL/kg). The rats in the sham group and SAH group were injected with equal volumes of sodium chloride injection. The SAH score and neurological score were performed 24 h after SAH, and the water content in the brain tissue and Evans blue exudation rate were measured. The expressions of HMGB1, SIRT1 and acetylated HMGB1 proteins in the brain tissue of rats were detected by Western Blot. The expression of HMGB1 mRNA in the brain of the rats was detected by quantitative real-time PCR. The distribution of HMGB1 protein in the brain of the rats was observed by immunofluorescence staining. TUNEL staining was used to observe the neuronal apoptosis in the brain tissue of the rats. Results:Compared with the SAH group, the SAH score of the OA group was significantly reduced ( P<0.001), the Garcia score was increased ( P<0.01), and the brain water content and Evans blue exudation rate were both reduced (all P<0.01). Compared with the OA group, the SAH score of the Sirtinol group was increased ( P<0.01), the Garcia score was significantly decreased ( P<0.001), and the brain water content and Evans blue exudation rate were both increased (all P<0.01). The results of Western Blot and real-time fluorescent quantitative PCR showed that, compared with the SAH group, the protein level ( P<0.01) and mRNA level ( P<0.05) of HMGB1 in the OA group were decreased, the expression of SIRT1 protein was significantly increased ( P<0.001), and the expression of acetylated HMGB1 protein was decreased ( P<0.01). Immunofluorescence staining showed that OA inhibited the migration of HMGB1 protein from the nucleus to the cytoplasm. TUNEL staining showed that OA could effectively reduce the number of TUNEL-positive cells. Compared with the OA group, Sirtinol significantly increased the number of TUNEL-positive cells. Conclusions:OA can reduce the release of HMGB1 through the SIRT1/HMGB1 pathway, thereby protecting the early brain injury after SAH.

9-Hydroxy-6,7-dimethoxydalbergiquinol suppresses hydrogen peroxide-induced senescence in human dermal fibroblasts through induction of sirtuin-1 expression

Objective:To investigate the potential anti-aging mechanism of 9-hydroxy-6,7-dimethoxydalbergiquinol (HDDQ) on hydrogen peroxide (H2O2)-induced oxidative stress in human dermal fibroblasts (HDFs). Methods:The effect of HDDQ on cell viability was assessed by MTT assay, and the effects of HDDQ on senescence-like phenotypes were determined by senescence-associated β-galactosidase (SA-β-gal) staining, Western blotting analysis, and a cell proliferation assay. The expression level and activity of sirtuin-1 (SIRT1) induced by HDDQ were also measured. Results:HDDQ reversed senescence-like phenotypes in the oxidant-challenged model, through reducing SA-β-gal activity and promoting cell growth. Meanwhile, decreases in ac-p53, p21Cip1/WAF1, and p16Ink4a and an increase in pRb were observed. HDDQ induced the expression of SIRT1 in a concentration- and time-dependent manner. Moreover, HDDQ inhibited H2O2-induced phosphorylation of Akt by SIRT1 up-regulation and reduced SA-β-gal staining. Conclusions:HDDQ inhibits H2O2-induced premature senescence and upregulation of SIRT1 expression plays a vital role in the inhibition of the senescence phenotype in HDFs.

Resveratrol in Alzheimers disease: a review of pathophysiology and therapeutic potential / Resveratrol na doença de Alzheimer: uma revisão sobre fisiopatologia e potencial terapêutico

ABSTRACT Background: Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressive and irreversible loss of cognitive function. The presence of senile plaques is one of the pathological markers of the disease and is associated with the onset of neuroinflammatory mechanisms. The exact pathophysiology of AD has not been completely understood, and there are no curative therapies yet. Resveratrol (3,5,4'-trihydroxy-trans-stilbene) is a polyphenol that is noted for its antioxidant and anti-inflammatory properties. Objective: To review the role of resveratrol in the pathophysiological aspects of AD. Methods: This study carried out a literature review using PubMed/Medline, Virtual Health Library (VHL), Web of Sciences, SCOPUS and the Cochrane Library databases. Original research articles, describing both in vitro and in vivo experiments, published between 2008 and 2018, were included. Results: We identified 667 articles, of which 619 were excluded because they were repeated or did not follow the inclusion criteria. The present study includes the remaining 48 articles. Discussion: Resveratrol demonstrates beneficial and protective effects in AD models and seems to provide a promising therapeutic alternative. Conclusion: Although resveratrol appears to mitigate some pathophysiological aspects of AD, further studies are needed to prove the safety and efficacy of this compound in humans.

RESUMO Introdução: A doença de Alzheimer (DA) é neurodegenerativa e caracterizada por perda progressiva e irreversível da função cognitiva. A presença de placas senis é um dos marcadores patológicos da doença e está associada ao aparecimento de mecanismos neuroinflamatórios. A fisiopatologia exata da DA ainda não é completamente compreendida, e ainda não existem terapias curativas. O resveratrol (3,5,4'-trihidroxi-trans-estilbeno) é um polifenol conhecido por suas propriedades antioxidantes e anti-inflamatórias. Objetivo: Revisar o papel do resveratrol nos aspectos fisiopatológicos da DA. Métodos: Este estudo realizou uma revisão narrativa da literatura a partir das bases de dados PubMed/Medline, Biblioteca Virtual em Saúde (BVS), Web of Science, SCOPUS e Cochrane Library. Foram incluídos artigos originais, realizados in vitro e in vivo, publicados entre 2008 e 2018. Resultados: Foram identificados 667 artigos, dos quais 619 foram excluídos por estarem repetidos ou não se enquadrarem nos critérios de inclusão. O presente estudo inclui os 48 artigos restantes. Discussão: O resveratrol demonstra efeitos benéficos e protetores em modelos de DA, bem como parece fornecer uma alternativa terapêutica promissora. Conclusão: Embora o resveratrol pareça atenuar alguns aspectos fisiopatológicos da DA, são necessários mais estudos para comprovar a segurança e a eficácia deste composto em seres humanos.

Testosterone antagonizes paraquat-induced cardiomyocyte senescence via the mIGF-1/SIRT1 signaling pathway

Testosterone has been demonstrated to antagonize doxorubicin-induced cardiomyocyte senescence. However, whether testosterone prevents the paraquat-induced cardiomyocyte senescence is largely unknown. The detection of SA-β-gal activity was performed using senescence β-gal staining kit and the reactive oxygen species levels were determined by reactive oxygen species assay kit. The plasmids for insulin-like growth factor 1 shRNA (sh-mIGF-1), sirtuin-1 shRNA (sh-SIRT1), scramble shRNA (sh-NC), overexpressing mIGF-1 (mIGF-1), overexpressing SIRT1 (SIRT1), and negative controls (NC) were obtained for this study. The expression of target genes was detected using quantitative real-time PCR, immunolabeling, and western blot. We found that testosterone significantly delayed the paraquat-induced HL-1 cardiomyocyte senescence as evidenced by decreasing senescence-associated β-galactosidase activity and reactive oxygen species generation, which were accompanied by the up-regulated expression of mIGF-1 and SIRT1. RNA interference to reduce mIGF-1 and SIRT1 expression showed that testosterone prevented paraquat-induced HL-1 senescence via the mIGF-1/SIRT1 signaling pathway. Furthermore, myocardial contraction was evaluated by expression of genes of the contractile proteins/enzymes, such as α-myosin heavy chain 6 (MHC6), α-myosin heavy chain 7 (MHC7), α-skeletal actin (ACTA-1), and sarco/endoplasmic reticulum calcium ATPase-2 (SERCA2). Testosterone adjusted the above four gene expressions and the adjustment was blocked by mIGF-1 or SIRT1 inhibition. Our findings suggested that the mIGF-1/SIRT1 signaling pathway mediated the protective function of testosterone against the HL-1 cardiomyocyte senescence by paraquat, which provided new clues for the mechanisms underlying the anti-aging role of testosterone in cardiomyocytes.

Inhibition of miR-383 suppresses oxidative stress and improves endothelial function by increasing sirtuin 1

Previous research has shown that suppression of miR-383 can prevent inflammation of the endothelium, as well as postpone the development of atherosclerosis. However, the role of miR-383 in endothelial cell apoptosis in diabetes remains unclear. The aim of this study was to investigate the function of miR-383 in high glucose-induced apoptosis and oxidative stress in endothelial cells. A series of experiments involving qualitative polymerase chain reaction, cell transfection, luciferase assay, assessment of cell death, detection of catalase and superoxide dismutase concentrations, detection of intracellular reactive oxygen species (ROS), and western blot analysis were performed in this study. We found that miR-383 expression was promoted, while NAD+-dependent deacetylase and sirtuin 1 (SIRT1) expressions were suppressed in the endothelium of the aorta in db/db mice as well as in human umbilical vein endothelial cells, which were treated with high glucose (HG). Increased expression of miR-383 decreased expression of SIRT1, while suppression of miR-383 promoted expression of SIRT1 in human umbilical vein endothelial cells (HUVECs). Furthermore, suppression of miR-383 following transfection with miR-383 suppressor repressed cell death and generation of ROS in HUVECs. SIRT1 knockdown by siRNA-SIRT1 reversed the suppressive effect of miR-383 inhibition on ROS production and cell apoptosis induced by HG treatment. Overall, the findings of our research suggested that suppression of miR-383 repressed oxidative stress and reinforced the activity of endothelial cells by upregulation of SIRT1 in db/db mice, and targeting miR-383 might be promising for effective treatment of diabetes.

Role of SIRT1 in hematologic malignancies / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Sirtuin 1 (SIRT1) is a protein deacetylase, which regulates various physiological activities by deacetylating different protein substrates. An increasing number of studies have revealed critical roles of SIRT1 in different aspects of cancers including metabolism, proliferation, genomic instability, and chemotherapy resistance. Depending on the protein targets in a certain oncogenic context, SIRT1 may play a unique role in each individual blood cancer subtype. Our previous work showed that activation of SIRT1 in primitive leukemia cells of acute myeloid leukemia (AML) and chronic myelogenous leukemia (CML) promotes disease maintenance. On the other hand, an SIRT1 agonist was shown to disrupt maintenance of myelodysplastic syndrome (MDS) stem cells and holds promise as a potential therapeutic approach. Herein, we present a concise summary of the different functions of SIRT1 in hematologic malignancies.