Syringin alleviates hepatic fibrosis by enhancing autophagic flux and attenuating ER stress-TRIB3/SMAD3 in diabetic mice.

Type 2 diabetes mellitus (T2DM) is a key risk factor for the developing of metabolic liver injury and easily evolving to advanced fibrosis. Syringin (SYR), isolated from Acanthopanax senticosus, has anti-inflammatory, anti-oxidant, and anti-apoptotic properties. However, its hepatoprotective effects and mechanisms in T2DM-induced liver fibrosis remain unclear. Here, we investigated whether syringin (SYR) could serve as a therapeutic agent for liver fibrosis and its mechanism in high-fat diet (HFD)/streptozotocin (STZ)-induced type 2 diabetic mice. C57BL/6 mice were induced with T2DM via HFD and STZ injection and treated with different doses of SYR. Serum lipid parameters and liver function indicators were measured, and hepatic histology and fibrosis were examined. The mechanism of SYR was explored through molecular analyses Results demonstrated SYR improved oral glucose tolerance, decreased the levels of ALT, AST, and AKP, and reduced hepatic lipid deposition in diabetic mice. Moreover, SYR ameliorated epithelial-to-mesenchymal transition to reverse hepatic fibrosis via suppressing TRIB3-SMAD3 interaction to restrain nuclear localization of SMAD3. Strikingly, SYR reversed hyperglycemia-induced deficiency in autophagic flux by regulation of Raptor/mTORC1, triggering nuclear translocation of TFEB to improve autophagosome-lysosomal fusion. In brief, SYR potentially ameliorates hepatic injury and fibrosis by enhancing autophagic flux and inhibing TRIB3 activation in diabetic mice.

Aucubin supplementation alleviate diabetes induced-disruption of blood-testis barrier and testicular damage via stabilizing cell junction integrity.

Disruption of blood-testis barrier (BTB) was a crucial pathological feature of diabetes induced-testicular injury at early phase. Aucubin (AU), a main active component in Eucommiae Cortex, has drawn attention for its benefits against male reproductive system disease. The current study was aimed at investigating the protective role of AU and exploring the underlying mechanism in diabetic model. A murine model of type 2 diabetes mellitus (T2DM) was induced by high-fat diet (HFD) combined with streptozocin (STZ). Testicular weight index and morphology, sperm quality, integrity of BTB and protein levels were analyzed. The underlying mechanism of the protective effect of AU was further explored in Sertoli cells (SCs) cultured with high glucose (HG). Our results showed AU inhibited testicular structural destruction, restored disruption of BTB and improved abnormal spermatogenic function in diabetic mice. Consistent with in vivo results, HG induced decreased transcellular resistance and increased permeability in SCs monolayers, while AU exposure reverses this trend. Meanwhile, reduced expression of Zonula occludin-1(ZO-1) and Connexin43(Cx43) in testicular tissue diabetic mice and HG-induced SCs was prominently reversed via AU treatment. Mechanistic studies suggested a high affinity interaction between AU and c-Src protein was identified based on molecular docking, and the activation of c-Src was significantly inhibited in AU treatment. Furthermore, AU significantly increased the expression of Cx43 and ZO-1 proteins HG-induced SCs, which can be further enhanced in gene-silenced c-Src cells to some extent. Our results suggested that AU ameliorated disruption of BTB and spermatogenesis dysfunction in diabetic mice via inactivating c-Src to stabilize cell junction integrity.

Aucubin ameliorates liver fibrosis and hepatic stellate cells activation in diabetic mice via inhibiting ER stress-mediated IRE1α/TXNIP/NLRP3 inflammasome through NOX4/ROS pathway.

Type 2 diabetes (T2DM) is closely associated with hepatic injury, which could promote/exacerbate hepatic inflammation, steatosis, and accelerate liver fibrosis progression. Aucubin (AU), as an active ingredient isolated from Eucommia ulmoides, exists a nutritional value in hepatoprotective effect and diabetic complications. However, whether it possesses more outstanding features on improving liver injury in diabetic conditions and the underlying mechanism is unclear. Our research investigated the treatment of AU on liver fibrosis and potential mechanisms on high-fat diet/streptozotocin-induced diabetic mice and high glucose (HG)&TGF-ß1-induced LX-2 cells. Results showed that AU restored hepatic function without affecting blood sugar levels in diabetic mice. Meanwhile, the enhanced levels of total cholesterol, triglycerides, and LDL-c were reversed in hepatic tissue after AU treatment. Histomorphology assays including H&E, Masson, PAS, Oil red and Sirius red staining showed that AU treatment reduced liver swelling, steatosis and fibrosis. Mechanistic studies showed that AU alleviated NLRP3 inflammasome activation and inflammatory responses via inhibiting ER stress-mediated IRE1α/TXNIP signaling pathway, which could postpone the development of T2DM induced hepatic fibrosis. In addition, the ROS generation and the up-regulated expression of NADHP oxidase 4 (NOX4) in the liver tissue were suppressed by AU treatment. Moreover, in vitro model, NOX4 activation was prominently enhanced and AU treatment blocked HG&TGF-ß1-induced NOX4 derived superoxide generation and thereby ameliorating hepatic stellate cell activation, which can be abrogated in the overexpression of NOX4 LX-2 cells. In addition, inhibition effects on ER stress-mediated IRE1α/TXNIP/NLRP3 inflammasome by AU treatment also were abolished in the overexpression of NOX4 LX-2 cells. Meanwhile, molecular docking results indicated that AU and NOX4 protein have a higher affinity. Taken together, AU might be a potential nutraceutical or therapeutic drug to ameliorate hepatic impairment and fibrosis in T2DM.

Complanatoside A targeting NOX4 blocks renal fibrosis in diabetic mice by suppressing NLRP3 inflammasome activation and autophagy.

BACKGROUND: Diabetic nephropathy (DN) is an important cause of end-stage renal disease. Complanatoside A (CA), an active component from Semen Astragali Complanati, has been reported to be a potential candidate for the treatment of kidney diseases. However, the underlying mechanisms and protective effects of CA in DN remain unclear. PURPOSE: In this paper, the effects and the mechanism of CA against ameliorating DN were investigated in vivo and in vitro. STUDY DESIGN: Here, a high-fat diet/streptozotocin-induced diabetic model and TGF-ß1-induced HK-2 cells were used to explore the protective effects and mechanisms of CA on DN in vivo and in vitro. METHODS: Major biochemical indexes, Histopathological morphology, and Immunohistochemistry have explored the therapeutic effect of CA on DN. Subsequently, TGF-ß1-induced HK-2 cells were utilized to investigate the anti-renal fibrosis effect of CA. Finally, the mechanism of CA against renal fibrosis was studied via western blotting, immunofluorescence, transfection, and molecular docking. RESULTS: The results showed that CA attenuated glomerular hypertrophy, collagen matrix deposition, and tubular interstitial fibrosis in diabetic mice. Moreover, the activation of TGF-ß1-inducible epithelial-mesenchymal transition (EMT) was hindered by CA treatment in HK-2 cells. Mechanistically, the data suggested that upregulated NOX4 during diabetes and TGF-ß1 in HK-2 cells was prominently diminished after CA treatment. Furthermore, CA exposure inhibited NLRP3 inflammasome activation and downstream inflammation gene expression such as IL-18 and IL-1ß in vivo and vitro. These findings indicated that CA obstructed the EMT to protect renal tubular epithelial cells against fibrosis via blocking NLRP3 activation, which was associated with inhibiting NOX4. Besides, the markedly raised autophagy levels in the diabetic model characterized by increasing LC3II/LC3I and Beclin1 were reversed after CA treatment, which is also a pivotal mechanism against renal fibrosis. More importantly, specific NOX4 overexpressed in HK-2 cells abolished that CA exposure blocked TGF-ß1-induced-EMT, ROS generation, NLRP3, and autophagy activation. Meanwhile, the inhibition of cell migration, ROS generation, autophagy, and renal inflammation after CA treatment was more pronounced in NOX4-deficient HK-2 cells. CONCLUSION: Our findings provided evidence that CA might be a potential therapeutic agent for DN by ameliorating NLRP3 inflammasome and autophagy activation via targeting NOX4 inhibition.

[Effect of cordycepin on CX43 expression in the corpus cavernosum of type II diabetes induced erectile dysfunction in rats].

OBJECTIVE: To study the effect of cordycepin on the expression of connexin 43 (CX43) in the corpus cavernosum tissue of the ED rats with type II diabetic mellitus (DM). METHODS: Forty male SD rats were fed with high-fat diet and injected intraperitoneally with STZ solution to induce type II DM, and then divided into 4 groups of an equal number: DM model control, low-dose cordycepin (10.0 mg/kg/d), high-dose cordycepin (30.0 mg/kg/d) and sildenafil positive control (5.0 mg/kg/d). Another 10 male SD rats were taken as blank controls and fed with normal diet. After 6 weeks of intervention, the sexual behavior of the rats was observed, the ratio of intra-cavernous pressure to mean arterial pressure (ICP/MAP) measured, and the corpus cavernosal tissue harvested for observation of the morphology and determination of the expression level of CX43 in the corpus cavernosum by immunohistochemistry. RESULTS: Compared with the DM model controls, the rats in the high-dose cordycepin group showed significantly improved latency and frequency of captures (P < 0.01), increased ICP/MAP ratio (P < 0.05), and improved morphology of the corpus cavernosal tissue. The expression of CX43 was found mainly in the smooth muscle cells of the penile corpus cavernosum, and dramatically higher in the high-dose cordycepin group than in the DM model controls (P < 0.01). CONCLUSION: Cordycepin can effectively improve the erectile function of type Ⅱ diabetic rats by up-regulating the expression of CX43 in the penile corpus cavernosum.

Cordycepin, a major bioactive component of Cordyceps militaris, ameliorates diabetes-induced testicular damage through the Sirt1/Foxo3a pathway.

Diabetes-induced male dysfunction is considered as a worldwide challenge, and testicular damage mainly caused by oxidative stress is its most common manifestation. Cordycepin, a natural antioxidant, has been used in the treatment of diabetic complications. However, the protective action and underlying mechanism of cordycepin on hyperglycaemia-induced testicular damage are unclear. This study aimed to investigate the protective effects and molecular mechanisms of cordycepin against diabetes-induced testicular damage. The type 2 diabetes model was established in C57BL/6 male mice via high-fat diet for 4 weeks and injected intraperitoneally with 50 mg/kg/day streptozotocin for five consecutive days. Then mice were treated with cordycepin (10 and 20 mg/kg, respectively) for 8 weeks. At the end of experiment, biochemical indicators, microstructure of testicular tissue, sperm morphology, TUNEL staining and protein expressions were evaluated. In the present study, cordycepin alleviated the testicular damage, restored disruption of the blood-testis barrier, and improved spermatogenic function via the antiapoptotic and antioxidant capacity. Mechanistically, cordycepin significantly enhanced SIRT1 expression and triggered the activity of Foxo3a, further to induce the expression of its downstream antioxidant enzymes, including Mn-SOD and CAT. These findings indicated that cordycepin could improve hyperglycaemia-induced testicular damage by regulating downstream antioxidant enzymes activity through the SIRT1/Foxo3a signalling pathway.

Dioscorea zingiberensis ameliorates diabetic nephropathy by inhibiting NLRP3 inflammasome and curbing the expression of p66Shc in high-fat diet/streptozotocin-induced diabetic mice.

OBJECTIVES: Diabetic nephropathy (DN) is a severe diabetic complication. Dioscorea zingiberensis (DZ) possesses excellent pharmacological properties with lower toxicity. The purpose of this study was to investigate the efficacy and mechanism of DZ in DN. METHODS: DN was established by the high-fat diet combining intraperitoneal injection of streptozotocin in mice. The DZ (125 and 250 mg/kg/day) were intragastrical administered for 8 consecutive weeks. After treatment, blood, urine and kidney tissue were collected for biological detection, renal morphology, fibrosis and molecular mechanism research, respectively. KEY FINDINGS: This study has shown that DZ significantly ameliorated kidney hypertrophy, renal structural damage and abnormal function of the kidney indicators (creatinine, urinary protein and blood urea nitrogen). Further molecular mechanism data suggested that the NLRP3/Cleaved-caspase-1 signal pathway was remarkably activated in DN, and DZ treatment reversed these changes, which indicated that it effectively attenuated inflammatory response caused by hyperglycaemia. In addition, DN inhibits hyperglycaemia-induced activation of oxidative stress by suppressing the expression of p66Shc proteins. CONCLUSIONS: DZ could efficiently suppress oxidative stress and inflammatory responses to postpone the development of DN, and its mechanism might be related to inhibition of NLRP3 and p66Shc activities. Thus, DZ could be developed into a new therapeutic agent for DN.

ß-elemonic acid inhibits growth and triggers apoptosis in human castration-resistant prostate cancer cells through the suppression of JAK2/STAT3/MCL-1 and NF-ĸB signal pathways.

Castration-resistant prostate cancer (CRPC) has become a significant problem in the current treatment of prostate cancer (PCa) with the characteristics of high metastatic potential, resistance and easy recurrence. The abnormal activation of JAK2/STAT3/MCL-1 and NF-κB has been confirmed as the main reason for the development of CRPC. We previously found that ß-elemonic acid (ß-EA) as a natural triterpene has potential anti-inflammatory and anti-osteosarcoma effects with lower toxicity. But it remains unknown whether it had effects on CRPC. The present research in vitro and in vivo systematically investigates anti-cancer effects and mechanisms of ß-EA on human CRPC. ß-EA treatment resulted in apoptotic cell death in human PCa cells by mitochondrial apoptotic pathways (including up-regulation of cleaved caspase-3, cleaved PARP, and Bax or down-regulation of Bcl-2). Besides, ß-EA at relatively lower levels inhibited colony-forming, the migration and invasion potential of PCa cells, indicating its anti-proliferation and anti-metastasis activities. After exploring the potential mechanism, our results suggested that it subsequently inhibited the activation of JAK2/STAT3/MCL-1 and NF-κB signaling pathway by the administration of ß-EA. The silencing of NF-κB/p65, JAK2 and STAT3, respectively, increased the sensitivity of the PCa cells to ß-EA induced apoptosis. Moreover, ß-EA exhibited a strong affinity with its essential proteins JAK2, RELA/p65, NF-κBIα/IκBα by molecular docking analysis. Importantly, ß-EA retards tumor growth in a murine xenograft model, consistent with our study in vitro. Taken together, findings from this study reveal for the first time the potential role and mechanisms of ß-EA on CRPC.

Aucubin, a natural iridoid glucoside, attenuates oxidative stress-induced testis injury by inhibiting JNK and CHOP activation via Nrf2 up-regulation.

BACKGROUND: Eucommia ulmoides has been used for many years as a successful strategy to treat male infertility. Aucubin (AU) is the active ingredient extracted from Eucommia ulmoides. However, its protective action and exact mechanism on testicular injury is not yet known. PURPOSE: Here, the protective effect and the mechanism of action of AU on testis damage under oxidative stress was investigated in vivo and in vitro. METHODS: As regard the in vivo experiment, male mice were divided into five groups and testicular injury model was established by Triptolide (TP) (120 µg/kg) intraperitoneal injection for two weeks. Animals in the treatment group were pretreated with an intraperitoneal injection of AU at different doses (5, 10 and 20 mg/kg) for 1 h and subsequently treated with TP (120 µg/kg). At the end of the experimental period, the testis was collected for biochemical and histological examination. As regard the in vitro experiment, Sertoli cells (SCs) were used to investigate the protective effect and mechanism of action of AU against disruption of the blood-testis-barrier (BTB) and apoptosis induced by TP via apoptosis detection, western blot, immunofluorescence analysis, and siRNA transient transfection. RESULTS: TP-treated animals showed testicular atrophy, BTB disruption, increased ROS levels and spermatogenic dysfunction. Pre-administration of AU resulted in a significant protection on keeping a normal testicular weight, sperm morphology, BTB integrity, and a normal level of oxidative stress markers and antioxidants. Furthermore, AU prevented apoptosis through an effective inhibition of PERK/CHOP and JNK dependent apoptosis pathway, as well as protected the integrity of BTB by up-regulating the expression of tight junction proteins (ZO-1, Occludin, Claudin-11) and gap junction protein (Cx43). The mechanistic study revealed that AU significantly triggered Nrf2 translocation, thus increasing nuclear Nrf2 accumulation and then induced antioxidant enzymes expression in the testis and SCs. Furthermore, Nrf2 silencing unsuccessfully reversed the increased CHOP and p-JNK expression induced by TP, abolishing the protective effect of AU. CONCLUSION: These results indicate that AU might be considered as a potential protective agent against testicular injury.

Single-walled carbon nanotubes used as stationary phase in GC.

Single-walled carbon nanotubes (SWNTs) have high surface area, high adsorption ability, and nanoscale interactions. In this study, capillary columns including SWNTs, ionic liquid (IL), and IL + SWNTs for GC were prepared. The separation results showed that SWNTs possessed a wide selectivity toward alkanes, alcohols, aromatic compounds, and ketones, and a SWNT capillary column was a very useful GC column for the separation of gas samples. Coating the IL stationary phase on the SWNT capillary column, the SWNTs were able to improve chromatographic characteristic of ionic liquid. Comparing the IL coated on three graphite carbon black capillary columns, which were prepared by dynamic coating, static coating, and chemical bonding the Carbopack C with on SWNTs capillary column, the capacity factors were much higher on the SWNT column. The SEM showed that SWNTs could be bonded to the inner surface of capillary tubing, and most of them were linked end-to-end to form a layer of network structure of skeletons resulting in a high surface area, which increased the interactions between stationary phase and analytes. This is the first single-wall carbon nanotubes bonded to the fused-silica capillary tubing. In the first approach, SWNTs assist ionic liquid with enhanced chromatographic characteristic in GC. This work indicates that SWNTs make it possible to extend the application range on the newly prepared chromatographic stationary phases for GC.