摘要
ObjectiveTo explore the molecular mechanism of modified Shengjiangsan in alleviating endoplasmic reticulum （ER） stress and reducing urinary protein in the rat model of diabetic nephropathy （DN）. MethodSeventy-five SD rats were randomized into normal， model， low-， medium-， and high-dose （4.37， 8.73， 17.46 g·kg-1， respectively） modified Shengjiangsan， and irbesartan （0.014 g·kg-1） groups， with 10 rats in each group. Rats were administrated with corresponding doses of medications or distilled water by gavage， once a day， for 8 consecutive weeks. After the last administration， the levels of glucose （GLU） in the blood， 24-hour urinary protein （24 h-UTP）， and superoxide dismutase （SOD）， malondialdehyde （MDA）， and glutathione peroxidase （GSH-Px） in the renal tissue were measured. Hematoxylin-eosin staining， periodic acid-Schiff staining， and transmission electron microscopy were employed to observe the pathological changes in rat kidneys. Immunohistochemistry was employed to measure the expression levels of nephrin， podocin， glucose-regulated protein 78 （GRP78）， C/EBP homologous protein （CHOP）， and activating transcription factor 4 （ATF4） in the kidneys of rats. Western blot was employed to measure the protein levels of silent information regulator 1 （Sirt1）， phosphorylated （p）-protein kinase RNA-like endoplasmic reticulum kinase （PERK）， and p-eukaryotic translation initiation factor 2 alpha （eIF2α） in rat kidneys. ResultCompared with the normal group， the modeling caused pathological damage to the kidneys， elevated the levels of GLU and 24 h-UTP （P<0.05）， up-regulated the protein levels of GRP78， CHOP， ATF4， p-PERK， and p-eIF2α （P<0.05）， and down-regulated the protein level of Sirt1 （P<0.05） in rat kidneys. Compared with the model group， modified Shengjiangsan and irbesartan lowered the GLU and 24 h-UTP levels （P<0.05）， alleviated the pathological damage in the renal tissue， down-regulated the protein levels of GRP78， CHOP， ATF4， p-PERK， and p-eIF2α （P<0.05）， and up-regulated the protein level of Sirt1 （P<0.05）. ConclusionModified Shengjiangsan up-regulates Sirt1 expression and inhibits phosphorylation of proteins in the PERK/eIF2α pathway to reduce ER stress and oxidative stress in the renal tissue， thus alleviating the pathological damage in the renal tissue and reducing urinary protein in DN rats.
摘要
ObjectiveTo explore the underlying mechanism by which the Chinese medicine compound Yitangkang granule（YTK） treats diabetic kidney disease （DKD） by observing its effects on podocyte autophagy through the regulation of phosphatidylinositol 3-kinase （PI3K）/protein kinase B （Akt）/forkhead transcription factor O1 （FoxO1） signaling pathway mediated by silent information regulator 1 （SIRT1） via advanced glycation end products （AGE）/receptor for AGE （RAGE） axis. MethodNinety-six 8-week-old healthy male SPF-grade Wistar rats were selected and randomly divided into blank control group （B）， model control group， high-dose YTK （40 g·kg-1）， medium-dose YTK （20 g·kg-1）， low-dose YTK （10 g·kg-1）， and Western medicine control （20 mg·kg-1 losartan） groups. The DKD rat model was established by high-fat diet feeding combined with intraperitoneal injection of streptozotocin. After successful modeling， the rats in each group received the corresponding treatments for eight weeks. The levels of superoxide dismutase （SOD）， malondialdehyde （MDA）， glutathione peroxidase （GSH-Px）， and catalase （CAT） were measured according to the instructions of the respective assay kits. Hematoxylin and eosin （HE） staining was used to observe pathological changes in kidney tissues. Immunohistochemistry was employed to detect the average optical density values of α-smooth muscle actin （α-SMA）， fibronectin （FN）， desmin， and nephrin. Western blot analysis was used to measure the expression levels of PI3K， phosphorylated PI3K （p-PI3K）， Akt， phosphorylated Akt （p-Akt）， RAGE， SIRT1， Caspase-3， and FoxO1 proteins in kidney tissues of DKD rats. ResultCompared with the blank control group， the model group showed significantly lower levels of SOD， GSH-Px， and CAT， and significantly higher levels of MDA （P<0.01）. The rats exhibited severe kidney damage. The positive expression of podocyte marker proteins α-SMA， FN， and desmin increased significantly， while nephrin and podocin significantly decreased （P<0.01）. The expression levels of PI3K， p-PI3K， Akt， p-Akt， RAGE， and Caspase-3 proteins were significantly elevated， while SIRT1 and FoxO1 protein levels were significantly reduced （P<0.01）. Compared with the model control group， rats in the YTK treatment groups showed significantly higher levels of SOD， GSH-Px， and CAT， and significantly lower levels of MDA in serum （P<0.01）. The degree of kidney damage was reduced to varying extents. The average optical density values of podocyte marker proteins α-SMA， FN， and desmin were significantly decreased， while nephrin and podocin significantly increased （P<0.01）. The expression levels of PI3K， p-PI3K， Akt， p-Akt， RAGE， and Caspase-3 in kidney tissues were significantly reduced， while SIRT1 and FoxO1 expression levels significantly increased （P<0.01）. The Chinese medicine groups demonstrated a clear dose-response trend. ConclusionYTK may alleviate kidney pathological damage， reduce proteinuria， and protect kidney function in DKD rats， thereby delaying the progression of DKD by improving podocyte autophagy through the AGE-RAGE axis-mediated SIRT1 regulation of the PI3K/Akt/FoxO1 signaling pathway. Additionally， a dose-response relationship was observed in the Chinese medicine groups.
摘要
ObjectiveTo investigate the protective effect and regulatory mechanism of berberine （BBR） against the senescence of ovarian granulosa cells. MethodA cell senescence model in the human ovarian granulosa-like tumor （KGN） cell line was induced by H2O2. A control group， a model group， and high-dose （1 μmol·L-1） and low-dose （0.5 μmol·L-1） BBR groups were set up. The cells in the model group and the BBR groups were incubated with 10 μmol·L-1 H2O2 for 40 min. The effect of BBR on KGN cell proliferation was detected by cell counting kit-8 （CCK-8） assay. The effect of BBR on the senescence of KGN cells was detected by β-galactosidase staining. The effects of BBR on the apoptosis and ROS content of KGN cells were detected by flow cytometry. The effects of BBR on the mRNA expression of B-cell lymphoma-2 （Bcl-2）/Bcl-2-associated X protein （Bax）， cysteinyl aspartate-specific protease-3 （Caspase-3）， forkhead transcription factor O1 （FoxO1）， and catalase （CAT） was detected by Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）. Western blot was used to detect the effects of BBR on protein expression of silent information regulator1 （SIRT1）， superoxide dismutase 2 （SOD2）， c-Jun N-terminal kinase （JNK）， FoxO1， autophagy-associated protein microtubule-associated protein light chain 3Ⅱ （LC3BⅡ）， mammalian ortholog of yeast Atg6 （Beclin-1）， and ubiquitin-binding protein p62. ResultAfter H2O2 induction for 40 min， the cell proliferation rate of the model group decreased compared with that of the control group （P<0.01）， and the cell proliferation rates of the BBR groups increased compared with that of the model group （P<0.05）. The results of β-galactosidase staining showed that the cells of the model group showed significant senescence compared with those of the control group （P<0.01）， and the cellular senescence in the BBR groups was reduced compared with that of the model group （P<0.01）. As revealed by flow cytometry， compared with the control group， the model group showed increased apoptosis rate （P<0.01）， and compared with the model group， BBR groups showed decreased apoptosis rates （P<0.05）. Meanwhile， the ROS content in the model group increased compared with that in the control group （P<0.01）， and compared with the model group， the BBR groups showed reduced cellular ROS content （P<0.01）. The Real-time PCR results showed that compared with the control group， the model group showed decreased mRNA expression of CAT and Bcl-2/Bax in KGN cells and increased mRNA expression of Caspase-3 and FoxO1 （P<0.05）， and compared with the model group， the BBR groups showed increased mRNA expression of CAT and Bcl-2/Bax （P<0.05） and reduced mRNA expression of Caspase-3 and FoxO1 in KGN cells （P<0.05）. As revealed by Western blot results， SIRT1， SOD2， and p62 protein levels decreased in the model group compared with those in the control group （P<0.01）， and JNK FoxO1， LC3BⅡ， and Beclin-1 protein levels increased （P<0.05）. After BBR intervention， SIRT1， SOD2， and p62 protein levels increased （P<0.01）， and JNK， FoxO1， LC3BⅡ， and Beclin-1 protein levels decreased compared with those in the model group （P<0.05）. ConclusionBBR has an inhibitory effect on ovarian granulosa cell senescence， and the mechanism is related to the inhibition of apoptosis and autophagy mediated by the SIRT1/FoxO1 pathway.
摘要
ObjectiveTo observe the effect of salvianolate on the protein expressions of adenosine monophosphate （AMP）-activated protein kinase （AMPK）， silent information regulator 1 （SIRT1） and peroxisome proliferator-activated receptor-γ coactivator-1α （PGC-1α）， autophagy and apoptosis in kidney tissue of rats with membranous nephropathy （MN）， and to explore its possible molecular mechanism against MN. MethodEighty male SD rats were randomly divided into normal group， model group， benazepril hydrochloride group （10 mg·kg-1）， and salvianolate low-， medium-， and high-dose groups （16.7， 33.3 and 66.7 mg·kg-1）. The rats were modeled by injection of cationized bovine serum albumin （C-BSA） into the tail vein. After successful modeling， rats in the administration groups were given corresponding doses of drugs for 4 consecutive weeks， and then 24-hour urine， serum and kidney tissue were collected for the detection of 24-hour urinary protein （UTP）， blood urea nitrogen （BUN）， serum creatinine （SCr）， interleukin-6 （IL-6）， tumor necrosis factor-α （TNF-α）， C reactive protein （CRP）， glutathione peroxidase （GSH-Px）， superoxide dismutase （SOD）， and malondialdehyde （MDA）. The pathological changes of kidneys were observed by light microscope， electron microscope and immunofluorescence. Western blot was used to detect the protein expressions of phospho-AMPK （p-AMPK）， AMPK， phospho-SIRT1 （p-SIRT1）， SIRT1 and PGC-1α in rat kidney tissue. The protein expressions of autophagy-specific gene （Beclin-1）， microtubule-associated protein 1 light chain 3 （LC3） Ⅱ， ubiquitin-binding protein （p62）， B cell lymphoma （Bcl-2）， Bcl-2-associated X （Bax）， and cysteine aspartic protease-7 （Caspase-7） in rat kidney tissue were determined by immunohistochemistry （IHC）. ResultCompared with the conditions in the normal group， the levels of UTP， IL-6， TNF-α， CRP and MDA in the model group were increased （P<0.05） while the levels of SOD and GSH-Px were decreased （P<0.05）， and there was no difference in BUN and SCr. Compared with the model group， the administration groups had lowered UTP， IL-6， TNF-α， CRP and MDA （P<0.05） while elevated SOD and GSH-Px （P<0.05）. It could be seen from hematoxylin and eosin （HE） staining， Masson staining， immunofluorescence and electron microscopy that the pathological damage of rat kidney tissue in the model group was significant， but after treatment with benazepril hydrochloride and salvianolate， the pathological damage of kidney cells was gradually improved. The expressions of p-AMPK/AMPK， p-SIRT1/SIRT1， PGC-1α， Bcl-2， Beclin-1 and LC3Ⅱ in rat kidney in the model group were lower than those in the normal group （P<0.05） while the expressions of Bax， Caspase-7 and p62 were higher （P<0.05）. Compared with the model group， benazepril hydrochloride group and salvianolate groups had an up-regulation in the expressions of p-AMPK/AMPK， p-SIRT1/SIRT1， PGC-1α， Bcl-2， Beclin-1 and LC3Ⅱ in the kidney （P<0.05） while a down-regulation in the expressions of Bax， Caspase-7 and p62 （P<0.05）. ConclusionThe protective effect of salvianolate on the kidneys of MN rats may be related to the activation of AMPK/SIRT1/PGC-1α signaling pathway， the up-regulation of autophagy and the reduction of apoptosis.
摘要
ObjectiveTo validate the alleviating effect of Gegen Qinliantang （GGQLT） on insulin resistance in db/db diabetic mice by regulating the silent information regulator 1 （SIRT1）/forkhead transcription factor O1 （FoxO1） autophagy pathway. MethodSeventy-five SPF-grade spontaneous type 2 diabetic db/db mice and 15 control db/m mice were selected and maintained on regular feed for one week before measuring blood glucose. They were randomly divided into six groups， with 15 mice in each group. The groups included a normal group （physiological saline， 0.2 g·kg-1）， a metformin group （0.2 g·kg-1）， high-， medium-， and low-dose GGQLT groups （31.9， 19.1， 6.9 g·kg-1）， and a model group （physiological saline， 0.2 g·kg-1）. They were orally treated with corresponding drugs for eight weeks， once daily. Fasting blood glucose （FBG） was measured using a Roche glucometer. Serum levels of high-density lipoprotein cholesterol （HDL-C）， low-density lipoprotein cholesterol （LDL-C）， triglyceride （TG）， and total cholesterol （TC） were measured using an automated biochemical analyzer. Fasting serum insulin （INS） levels were determined using enzyme-linked immunosorbent assay （ELISA）， and the homeostasis model assessment of insulin resistance （HOMA-IR） was calculated. Western blot was used to detect the expression of Beclin-1， microtubule-associated protein 1 light chain 3 （LC3）， and SIRT1/FoxO1 autophagy pathway-related proteins in liver tissues. Immunohistochemistry was performed to assess the expression of SIRT1， FoxO1， Beclin-1， and LC3B proteins in liver tissues. Transmission electron microscopy was used to observe the formation of autophagosomes in the liver. ResultCompared with the normal group， the model group showed significant increases in FBG， FINS， HOMA-IR， TC， TG， LDL-C， and HDL-C levels （P<0.01）， and significant increases in the expression of SIRT1， Beclin-1， LC3， and FoxO1 proteins in liver tissues （P<0.01）. Transmission electron microscopy revealed the highest number of autophagosomes in the model group. Compared with the model group， the metformin group and the low-， medium-， and high-dose GGQLT groups showed significant decreases in serum FBG， FINS， HOMA-IR， TC， TG， LDL-C， and HDL-C levels （P<0.05， P<0.01）， significant decreases in the expression of SIRT1， Beclin-1， LC3 （P<0.05， P<0.01）， and up-regulated FoxO1 protein （P<0.01）. Transmission electron microscopy showed a reduction in the degree of autophagy in the treatment groups. Compared with the metformin group， the medium- and high-dose GGQLT groups showed significant decreases in FBG， FINS， and TG levels （P<0.01）， significant decreases in the expression of SIRT1， Beclin-1， and LC3 in liver tissues （P<0.05， P<0.01）， and reduced FoxO1 protein （P<0.01）. The high-dose GGQLT group showed reduced HOMA-IR， TC， LDL-C， and HDL-C levels （P<0.05， P<0.01）. Transmission electron microscopy revealed a significant reduction in autophagosomes in the medium- and high-dose GGQLT groups. ConclusionGGQLT can significantly improve glucose and lipid metabolism disorders， alleviate insulin resistance in db/db mice， and prevent and treat type 2 diabetes by activating the SIRT1/FoxO1 autophagy pathway.
摘要
Myeloma bone disease (MBD) is one of the most common complications of multiple myeloma (MM). MBD is considered to be caused by the activation of osteoclasts and suppression of osteoblasts resulting from the involvement of neoplastic plasma cells and the change of bone marrow microenvironment. It may be a feasible way to improve the treatment of MBD by promoting osteogenic differentiation of bone marrow mesenchymal stem cell (BMSC), from which the osteoblasts mainly originate. Resveratrol (RES), a naturally occurring polyphenolic flavonoid compound, was reported to function in the modulation of bone metabolism. But the effects of RES on osteogenic differentiation of MM derived BMSC (MM-BMSC) and its underlying mechanism remains unknown. Totally 10 cases of MM-BMSCs were isolated, cultured and identified successfully in the present study. RES was found to promote osteogenic differentiation of MM-BMSC by alkaline phosphatase activity assay, qRT-PCR and alizarin red staining. SIRT1 was predicted to be the target gene of RES in promoting osteogenic differentiation with bioinformatic analysis. RES upregulated the expression of silent information regulator 1 (SIRT1) in MM-BMSC (P<0. 001) and its osteogenic differentiation was inhibited in the SIRT1 small interfering RNA (si-SIRT1) transfected group. Furthermore, the mRNA (P<0. 001) and protein (P<0. 01) expression of runt related transcription factor 2 (RUNX2) was increased in the RES treated group and decreased (mRNA P < 0. 01, protein P < 0. 05) in si-SIRT1 transfected group, respectively. In conclusion, resveratrol promotes osteogenic differentiation of MM-BMSCs via upregulating SIRT1/RUNX2 and seems to be a potential therapeutic agent to counteract bone disease in MM patients.
摘要
Objective To explore the effect and mechanism of miR-181a on sepsis-induced acute lung injury in mice by targeting silent information regulator 1 (SIRT1). Methods Lipopolysaccharide was used to induce the A549 cell model of acute lung injury. miR-181 inhibitor and inhibitor negative control (inhibitor NC) were transfected in the cells. Cecal ligation and puncture (CLP) was used to establish the mouse model of sepsis-induced acute lung injury. The mice were intravenously infused with miR-181a antagomir and antagomir NC. Then survival rate and wet-to-dry ratio of the lungs were examined, the targeting relationship between miR-181a and SIRT1 was tested by luciferase reporter assay, RT-PCR was used to detect the gene expression of miR-181a and SIRT1 in vitro and vivo. Western blotting was used to detect the protein level of SIRT1 in vitro and vivo, as well as the levels of apoptosis-related protein B-cell lymphoma-2 (Bcl-2), Bcl-2 associated X protein (Bax), and cleave caspase-3 (cl-CASP3). Cell apoptosis was quantified by flow cytometry, cell viability was measured by CCK-8, CASP3 activity was detected by kit. HE staining was used to observe the histopathological changes in the lungs; TUNNEL staining was used to detected the cell apoptosis in the lungs. The concentrations of inflammatory cytokines were measured by ELISA. Results In cellular experiments, compared with those in control group, the expression of miR-181a was increased and the expression of SIRT1 was decreased in LPS group (P<0.01). Meanwhile the cell apoptosis rate was increased, CASP3 activity was increased, and cell viability was decreased. Treatment by miR-181a inhibitor could reverse the changes of the above indicators (P<0.01). In animal experiments, compared with those in sham group, in CLP group the mice's survival rate was decreased, wet-to-dry ratio of the lungs was increased, significant pathological changes and cell apoptosis in the lungs could be observed. Meanwhile, the concentrations of inflammatory cytokines were increased, the protein levels of miR-181a, Bax and cl-CASP3 were increased, and the protein levels of SIRT1 and Bcl-2 were decreased (P<0.01). Treatment by miR-181a antagomir could reverse the changes of the above indicators (P<0.05, P<0.01). Conclusion miR-181a can be targeted to SIRT1, and inhibition of miR-181a expression can increase SIRT1 expression, there by protecting against acute lung injury induced by sepsis in mice.
摘要
Objective To investigate the role of SIRT1/PGC-1α pathway in the auditory cortex aging of guinea pigs with age-related hearing loss and whether the electroacupuncture can delay aging process of the auditory cortex in the aged guinea pigs induced by D-galactose through the regulation of SIRT1/PGC-1α pathway.Methods Thirty 4-month-old guinea pigs were randomly divided into three groups including the control group (n=10),D-galactose group (model group,n =10),and D-galactose and electroacupuncture group (electroacupuncture group,n =10).The elderly group (n=10) was composed of 18-month-old guinea pigs.The guinea pigs in model group and electroacupuncture group had been subcutaneously injected with D-galactose(300 mg· kg-1· d-1)for 6 weeks.Moreover,the guinea pigs in electroacupuncture group electroacupunctured at Tinggong and Yifeng for 15 minutes half an hour later once a day.After 6 weeks,the ABR threshold of guinea pigs in each group was detected.The mRNA and protein expression of SIR1 and PG-C-1α in auditory cortex of guinea pigs were detected by real -time fluoreacence quantitative PCR and Western Blot.Results There was a significant increase in the ABR threshold of the model group and elderly group (P＜0.001,compared with the control group),decrease in the electroacupuncture group (P＜0.001,compared with the model group),and no significant difference between model group and elderly group(P＞0.05).There was significant decrease in the expression of SIRT1 and PGC-1α in the model groupand elderly group(P＜0.05,compared with the control group),and significant increase at mRNA and protein levels in the electroacupuncture group (P＜0.05,compared with the model group).Conclusion SIRT1/PG-C-1α pathway may play a role in aging process of the auditory cortex in the aged guinea pigs induced by D-galactose,and electroacupuncture at Tinggong and Yifeng may increase the antioxidant capacity of auditory cortex by activating SIRT1/PGC 1α in guinea pigs with age-related hearing loss,thus delaying the aging process of auditory cortex.