Human amniotic mesenchymal stem cells-derived conditioned medium and exosomes alleviate oxidative stress-induced retinal degeneration by activating PI3K/Akt/FoxO3 pathway.

Age-related macular degeneration (AMD) is the leading cause of vision loss among the elderly, which is primarily attributed to oxidative stress-induced damage to the retinal pigment epithelium (RPE). Human amniotic mesenchymal stem cells (hAMSC) were considered to be one of the most promising stem cells for clinical application due to their low immunogenicity, tissue repair ability, pluripotent potential and potent paracrine effects. The conditional medium (hAMSC-CM) and exosomes (hAMSC-exo) derived from hAMSC, as mediators of intercellular communication, play an important role in the treatment of retinal diseases, but their effect and mechanism on oxidative stress-induced retinal degeneration are not explored. Here, we reported that hAMSC-CM alleviated H2O2-induced ARPE-19 cell death through inhibiting mitochondrial-mediated apoptosis pathway in vitro. The overproduction of reactive oxygen species (ROS), alteration in mitochondrial morphology, loss of mitochondrial membrane potential and elevation of Bax/Bcl2 ratio in ARPE-19 cells under oxidative stress were efficiently reversed by hAMSC-CM. Moreover, it was found that hAMSC-CM protected cells against oxidative injury via PI3K/Akt/FoxO3 signaling. Intriguingly, exosome inhibitor GW4869 alleviated the inhibitory effect of hAMSC-CM on H2O2-induced decrease in cell viability of ARPE-19 cells. We further demonstrated that hAMSC-exo exerted the similar protective effect on ARPE-19 cells against oxidative damage as hAMSC-CM. Additionally, both hAMSC-CM and hAMSC-exo ameliorated sodium iodate-induced deterioration of RPE and retinal damage in vivo. These results first indicate that hAMSC-CM and hAMSC-exo protect RPE cells from oxidative damage by regulating PI3K/Akt/FoxO3 pathway, suggesting hAMSC-CM and hAMSC-exo will be a promising cell-free therapy for the treatment of AMD in the future.

Association of blood urea nitrogen with all-cause and cardiovascular mortality in hyperlipidemia: NHANES 1999-2018.

OBJECTIVE: Although blood urea nitrogen (BUN) has a crucial impact on many diseases, its effect on outcomes in patients with hyperlipidemia remains unknown. The study aimed to investigate the relationships between BUN levels and all-cause and cardiovascular disease (CVD) mortality in individuals with hyperlipidemia. METHODS: This analysis comprised 28,122 subjects with hyperlipidemia from the National Health and Nutrition Examination Survey (NHANES) spanning 1999 to 2018. The risk of BUN on mortality was evaluated using weighted Cox regression models. Additionally, to illustrate the dose-response association, the restricted cubic spline (RCS) was used. RESULTS: During the observation period, 4276 participant deaths were recorded, of which 1206 were due to CVD. Compared to patients with hyperlipidemia in the third BUN quintile, the hazard ratios (HRs) for all-cause mortality were 1.26 (95% CIs: 1.09, 1.45) and 1.22 (95% CIs: 1.09, 1.37) for patients in the first and fifth quintiles of BUN, respectively. The HRs for CVD mortality among patients in the fifth quintile of BUN were 1.48 (95% CIs: 1.14, 1.93). BUN levels were found to have a U-shaped association with all-cause mortality and a linear association with CVD mortality using restricted triple spline analysis. CONCLUSIONS: This study revealed that both low and high BUN levels in patients with hyperlipidemia are associated with heightened all-cause mortality. Furthermore, elevated BUN levels are also associated with increased CVD mortality. The findings indicate that patients with hyperlipidemia may face an elevated risk of death if they have abnormal BUN levels.

Curcumin protects retinal neuronal cells against oxidative stress-induced damage by regulating mitochondrial dynamics.

Oxidative stress plays a crucial role in the damage of retinal neuronal cells. Curcumin, the phytocompound, has anti-inflammatory and antioxidative properties. It was shown that curcumin exerted a beneficial effect on retinal neuronal cell survival. However, the role of mitochondrial dynamics in curcumin-mediated protective effect on retinal neuronal cells remains to be elucidated. Here, H2O2 was used to mimic the oxidative stress in retinal neuronal R28 cells. Drp1 and Mfn2 are key regulators of mitochondrial fission and fusion. 100 µM of H2O2 significantly increased the cleavage of caspase-3 and Drp1 expression, but downregulated the expression of Mfn2. Pretreatment with 5 µM curcumin effectively alleviated H2O2-induced alterations in the expression of Drp1 and Mfn2 and mitochondrial fission in R28 cells. In addition, curcumin and Drp1 knockdown prevented H2O2-induced intracellular ROS increment and mitochondrial membrane potential disruption. On the contrary, knockdown of Mfn2 diminished curcumin-mediated protection against ROS increment and mitochondrial membrane potential disruption after H2O2. Moreover, curcumin protected R28 cells against H2O2-induced PINK1 expression, mitophagy, caspase-3 cleavage and apoptosis. Knockdown of Mfn2 significantly alleviated the protective effect of curcumin on R28 cells after H2O2. Taken together, our data indicate that curcumin protects against oxidative stress-induced injury in retinal neuronal cells by promoting mitochondrial fusion.

Gallbladder-preserving polypectomy for gallbladder polyp by embryonic-natural orifice transumbilical endoscopic surgery with a gastric endoscopy.

BACKGROUND AND AIMS: Cholecystectomy is performed for most gallbladder polyps (GPs). However, cholecystectomy results concerning complications in some patients. For benign GPs, adoption of gallbladder-preserving surgery is worth to recommend. We describe our experiences performing gallbladder-preserving polypectomy for GPs by embryonic-natural orifice transumbilical endoscopic surgery (E-NOTES) with a gastric endoscopy. METHODS: This is a retrospective study of patients with GPs who underwent gallbladder-preserving polypectomy by E-NOTES with a gastric endoscopy from April 2018 to September 2019 in our hospital. The operative time, intraoperative hemorrhage, intraoperative and postoperative complications, gallbladder emptying function were obtained and analyzed. RESULTS: The procedure was performed successfully in all 12 patients with 5 cases of single polyp and 7 cases of multiple polyps. The range of GPs size was 2 mm to 15 mm. The mean operation time was (95.33 ± 23.08) minutes (55-135 min). There were no adverse events including heavy bleeding, mortality and conversion to open surgery during operation. All patients were discharged in 4-5 days after surgery without postoperative complications such as delayed bleeding, fever, peritonitis, intra-abdominal abscess and abdominal wall incisional hernia. All patients were followed up at 1, 3, 6, and 12 months postoperation who had almost no visible incision on the umbilical region, no recurrent GPs. The gallbladder emptying function decreased one month after surgery, and gradually improved 3, 6 and 12 months after surgery. CONCLUSION: E-NOTES gallbladder-preserving polypectomy is a safe and effective option for patients with GPs and is close to scar-free surgery which can be performed in routine clinical practice.

RP5-833A20.1/miR-382-5p/NFIA-dependent signal transduction pathway contributes to the regulation of cholesterol homeostasis and inflammatory reaction.

OBJECTIVE: Cardiovascular disease caused by atherosclerosis is the number one cause of death in Western countries and threatens to become the major cause of morbidity and mortality worldwide. Long noncoding RNAs are emerging as new players in gene regulation, but how long noncoding RNAs operate in the development of atherosclerosis remains unclear. APPROACH AND RESULTS: Using microarray analysis, we found that long noncoding RNA RP5-833A20.1 expression was upregulated, whereas nuclear factor IA (NFIA) expression was downregulated in human acute monocytic leukemia macrophage-derived foam cells. Moreover, we showed that long noncoding RNA RP5-833A20.1 may decreases NFIA expression by inducing hsa-miR-382-5p expression in vitro. We found that the RP5-833A20.1/hsa-miR-382-5p/NFIA pathway is essential to the regulation of cholesterol homeostasis and inflammatory responses in human acute monocytic leukemia macrophages. Lentivirus-mediated NFIA overexpression increased high-density lipoprotein cholesterol circulation, reduced low-density lipoprotein cholesterol, and very-low-density lipoprotein cholesterol circulation, decreased circulation of inflammatory cytokines, including interleukin-1ß, interleukin-6, tumor necrosis factor-α, and C-reactive protein, enhanced reverse cholesterol transport, and promoted regression of atherosclerosis in apolipoprotein E-deficient mice. CONCLUSIONS: Our findings indicated that the RP5-833A20.1/miR-382-5p/NFIA pathway was essential to the regulation of cholesterol homeostasis and inflammatory reactions and suggested that NFIA may represent a therapeutic target to ameliorate cardiovascular disease.

The miR-573/apoM/Bcl2A1-dependent signal transduction pathway is essential for hepatocyte apoptosis and hepatocarcinogenesis.

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors with an increasing incidence worldwide. Apolipoprotein M (apoM) is a novel apolipoprotein that is mainly expressed in liver and kidney tissues. However, the anti-tumor properties of apoM remain largely unknown. We evaluated the anti-tumor activities and mechanisms of apoM in HCC both in vivo and in vitro. Bioinformatic analysis and luciferase reporter assay results showed that apoM was a potential target of hsa-miR-573 and was downregulated after transfection with hsa-miR-573 mimics. Overexpression of apoM suppressed migration, invasion, and proliferation of hepatoma cells in vitro. Overexpression of hsa-miR-573 in hepatoma cells reduced apoM expression, leading to promotion of the invasion, migration, and proliferation of hepatoma cells in vitro. In addition, hsa-miR-573 markedly promoted growth of xenograft tumors in nude mice with an accompanying reduction in cell apoptosis. ApoM markedly inhibited growth of xenograft tumors in nude mice and promoted cell apoptosis. Moreover, Bcl2A1 mRNA and protein levels were inhibited by apoM overexpression and an increase in apoptosis rate by apoM was markedly compensated by Bcl2A1 overexpression in HepG2 cells. These results provide evidence that hsa-miR-573 promoted tumor growth by inhibition of hepatocyte apoptosis and this pro-tumor effect might be mediated through Bcl2A1 in an apoM-dependent manner. Therefore, our findings may be useful to improve understanding of the critical effects of hsa-miR-573 and apoM in HCC pathogenesis.

A lincRNA-DYNLRB2-2/GPR119/GLP-1R/ABCA1-dependent signal transduction pathway is essential for the regulation of cholesterol homeostasis.

Accumulated evidence shows that G protein-coupled receptor 119 (GPR119) plays a key role in glucose and lipid metabolism. Here, we explored the effect of GPR119 on cholesterol metabolism and inflammation in THP-1 macrophages and atherosclerotic plaque progression in apoE(-/-) mice. We found that oxidized LDL (Ox-LDL) significantly induced long intervening noncoding RNA (lincRNA)-DYNLRB2-2 expression, resulting in the upregulation of GPR119 and ABCA1 expression through the glucagon-like peptide 1 receptor signaling pathway. GPR119 significantly decreased cellular cholesterol content and increased apoA-I-mediated cholesterol efflux in THP-1 macrophage-derived foam cells. In vivo, apoE(-/-) mice were randomly divided into two groups and infected with lentivirus (LV)-Mock or LV-GPR119 for 8 weeks. GPR119-treated mice showed decreased liver lipid content and plasma TG, interleukin (IL)-1ß, IL-6, and TNF-α levels, whereas plasma levels of apoA-I were significantly increased. Consistent with this, atherosclerotic lesion development was significantly inhibited by infection of apoE(-/-) mice with LV-GPR119. Our findings clearly indicate that, Ox-LDL significantly induced lincRNA-DYNLRB2-2 expression, which promoted ABCA1-mediated cholesterol efflux and inhibited inflammation through GPR119 in THP-1 macrophage-derived foam cells. Moreover, GPR119 decreased lipid and serum inflammatory cytokine levels, decreasing atherosclerosis in apoE(-/-) mice. These suggest that GPR119 may be a promising candidate as a therapeutic agent.

The mechanisms of natural products for eye disorders by targeting mitochondrial dysfunction.

The human eye is susceptible to various disorders that affect its structure or function, including glaucoma, age-related macular degeneration (AMD) and diabetic retinopathy (DR). Mitochondrial dysfunction has been identified as a critical factor in the pathogenesis and progression of eye disorders, making it a potential therapeutic target in the clinic. Natural products have been used in traditional medicine for centuries and continue to play a significant role in modern drug development and clinical therapeutics. Recently, there has been a surge in research exploring the efficacy of natural products in treating eye disorders and their underlying physiological mechanisms. This review aims to discuss the involvement of mitochondrial dysfunction in eye disorders and summarize the recent advances in the application of natural products targeting mitochondria. In addition, we describe the future perspective and challenges in the development of mitochondria-targeting natural products.

Natural Products in Liver Fibrosis Management: A Five-year Review.

Liver fibrosis, characterized by the overproduction of extracellular matrix proteins within liver tissue, poses a rising global health concern. However, no approved antifibrotic drugs are currently available, highlighting the critical need for understanding the molecular mechanisms of liver fibrosis. This knowledge could not only aid in developing therapies but also enable early intervention, enhance disease prediction, and improve our understanding of the interaction between various underlying conditions and the liver. Notably, natural products used in traditional medicine systems worldwide and demonstrating diverse biochemical and pharmacological activities are increasingly recognized for their potential in treating liver fibrosis. This review aims to comprehensively understand liver fibrosis, emphasizing the molecular mechanisms and advancements in exploring natural products' antifibrotic potential over the past five years. It also acknowledges the challenges in their development and seeks to underscore their potency in enhancing patient prognosis and reducing the global burden of liver disease.

XRCC1 Arg399Gln, Arg194Trp, and Arg280His polymorphisms in esophageal cancer risk: a meta-analysis.

BACKGROUND: The X-ray repair cross-complementation group 1 (XRCC1) protein plays an important role in base excision repair. AIM: To elucidate the role of XRCC1 Arg399Gln, Arg194Trp and Arg280His genotypes in esophageal cancer risk, all available studies were considered in the present meta-analysis. METHODS: Eligible studies were identified by searching several electronic databases for relevant reports published before June 2012. RESULTS: According to the inclusion criteria and exclusion criteria, a total of 21 eligible studies were included in the pooled analyses. Among the 21 studies, 18 focused on Arg399Gln polymorphism, 11 described the Arg194Trp, and 4 articles investigated on Arg280His. Our analysis suggested that there was no evidence of significant association between XRCC1 Arg399Gln polymorphism and esophageal cancer risk in any genetic model. In the stratified analysis by ethnicity for Arg399Gln polymorphism and esophageal cancer, the results showed that Arg399Gln polymorphism was not associated with esophageal cancer risk. Only 4 studies analyzed the relationship between XRCC1 Arg280His polymorphism and the risk of esophageal cancer. The Arg/His and His/His genotypes were not significantly associated with increased risk of EC. A similar negative association was maintained in dominant and recessive models. However, for XRCC1 Arg194Trp polymorphism, our study showed individuals carrying the variant genotype Trp/Trp had a significant increased risk of esophageal cancer (OR = 1.295, 95 % CI 1.053-1.591, P = 0.014). In addition, increased associations were found in recessive model (OR = 1.332, 95 % CI 1.093-1.624, P = 0.005). CONCLUSIONS: Our meta-analysis suggested that Arg194Trp Trp allele might act as a risk allele in its association with esophageal cancer.

ß-Subunit myristoylation is the gatekeeper for initiating metabolic stress sensing by AMP-activated protein kinase (AMPK).

The AMP-activated protein kinase (AMPK) is an αßγ heterotrimer that acts as a master metabolic regulator to maintain cellular energy balance following increased energy demand and increases in the AMP/ATP ratio. This regulation provides dynamic control of energy metabolism, matching energy supply with demand that is essential for the function and survival of organisms. AMPK is inactive unless phosphorylated on Thr172 in the α-catalytic subunit activation loop by upstream kinases (LKB1 or calcium-calmodulin-dependent protein kinase kinase ß). How a rise in AMP levels triggers AMPK α-Thr172 phosphorylation and activation is incompletely understood. Here we demonstrate unequivocally that AMP directly stimulates α-Thr172 phosphorylation provided the AMPK ß-subunit is myristoylated. Loss of the myristoyl group abolishes AMP activation and reduces the extent of α-Thr172 phosphorylation. Once AMPK is phosphorylated, AMP further activates allosterically but this activation does not require ß-subunit myristoylation. AMP and glucose deprivation also promote membrane association of myristoylated AMPK, indicative of a myristoyl-switch mechanism. Our results show that AMP regulates AMPK activation at the initial phosphorylation step, and that ß-subunit myristoylation is important for transducing the metabolic stress signal.

The neutrophil-to-lymphocyte ratio and lactate dehydrogenase combined in predicting liver metastasis and prognosis of colorectal cancer.

Background: The neutrophil-to-lymphocyte ratio (NLR) and lactate dehydrogenase (LDH) level are inflammatory markers related to tumor growth and metabolism. This study investigated the value of preoperative NLR, LDH and the combination of NLR and LDH (NLR-LDH) for predicting colorectal cancer liver metastasis (CRLM) and tumor prognosis in the early stages of colorectal cancer (CRC). Materials and methods: Three hundred patients undergoing CRC resection were included. Logistic regression analysis was used to estimate the correlation between CRLM time and inflammatory markers, and Kaplan-Meier survival and Cox regression analyses were used to estimate overall survival (OS). Forest plots were prepared based on the multivariate Cox analysis model and evaluated by receiver operating characteristic (ROC) curve analysis. Results: The NLR cut-off value was 2.071 according to the ROC curve. The multivariate analysis showed that the elevated LDH level and a high NLR-LDH level were independent predictors of synchronous CRLM and OS (p < 0.05). The combination of a high NLR and elevated LDH and NLR-LDH levels suggested a poor prognosis and a significantly shorter median survival time than a low NLR and low levels of LDH and NLR-LDH. The ROC curve analysis results illustrated that the predictive value of the NLR-LDH score for synchronous CRLM [area under the curve (AUC) = 0.623, p < 0.001] and OS (AUC = 0.614, p = 0.001) was superior to that of the NLR or LDH score used alone. Conclusion: LDH and NLR-LDH are reliable, easy-to-use, independent biomarkers for predicting synchronous or metachronous CRLM and OS in CRC patients. The NLR is an important monitoring index for CRLM. Preoperative NLR, LDH and NLR-LDH may help to guide the use of therapeutic strategies and cancer surveillance.

Electrochemical assembly of single-walled carbon nanotube/polypyrrole/tellurium/lead telluride multi-layer nanocomposite films for room-temperature flexible thermoelectric application.

With the complexity and diversification of thermoelectric (TE) application scenarios, it becomes increasingly difficult for single-component thermoelectric materials to satisfy practical demands. Therefore, recent researches have largely focused on the development of the multi-component nanocomposites, which are probably a good solution for the TE application of some materials that are not eligible when used alone. In this work, a seires of single-walled carbon nanotube (SWCNT)/polypyrrole (PPy)/tellurium (Te)/lead telluride (PbTe) multi-layer flexible composite films were fabricated via the successive electrodeposition of the flexible PPy layer with a low thermal conductivity, the ultra-thin Te induction layer, and the brittle PbTe layer with a large Seebeck coefficient over the pre-fabricated SWCNT membrane electrode with a high electrical conductivity. Through the complementary advantages between different components and the multiple synergies of the interface engineering, the SWCNT/PPy/Te/PbTe composites harvested the excellent TE performance with a maximum power factor (PF) of 929.8 ± 35.4 µW m-1 K-2 at room temperature, outperforming those of most of the electrochemically-prepared organic/inorganic TE composites reported previously. This work evidenced that the electrochemical multi-layer assembly is a feasible tactic for constructing special thermoelectric materials to meet customized requirements, which could also be applied to other material platforms.

Lactate protects against oxidative stress-induced retinal degeneration by activating autophagy.

Age-related macular degeneration is a common cause of blindless among the aged, which can mainly be attributed to oxidative stress and dysregulated autophagy in retinal pigment epithelium cells. Lactate was reported to act as a signaling molecule and exerted beneficial effect against oxidative stress. This study aims to investigate the protective effect of lactate against oxidative stress-induced retinal degeneration. Here, H2O2-induced oxidative stress cell model and sodium iodate-induced mice retinal degeneration model were established. It was found that H2O2 inhibited cell viability in ARPE-19 cells and sodium iodate induced deterioration of retinal pigment epithelium as well as apoptosis in retina. Pretreatment with lactate alleviated oxidative stress-induced cell death and retinal degeneration. Molecularly, lactate activated autophagy by up-regulating the ratio of LC3II/I, increased formation of LC3 puncta and autophagic vacuole. Further, lactate prevented H2O2-induced mitochondrial fission and maintained mitochondrial function by alleviating H2O2-induced mitochondrial membrane potential disruption and intracellular ROS generation. In contrast, application of 3-methyladenine, an inhibitor of autophagy, effectively weakened the protective effect of lactate against oxidative stress in vivo and in vitro. Taken together, all data in this study indicate that lactate protects against oxidative stress-induced retinal degeneration and preserves mitochondrial function by activating autophagy.

The complete chloroplast genome of Sloanea hemsleyana.

Sloanea hemsleyana is a potential commercial and oil tree species. This study is the first to report and analyze complete chloroplast genome sequences of S. hemsleyana as a genomic resource for conservation purposes. The chloroplast genome is 158,085 bp in length and consisted of a large single-copy (LSC) region (88,446 bp), and a small single-copy (SSC) region (17,659 bp), separated by a pair of inverted repeats (IR) regions (25,990 bp). It contains 108 genes, with 74 protein-coding genes, 30 tRNA genes, and 4 rRNA genes. Phylogenetic analysis revealed that S. hemsleyana was most closely related to S. sinensis.

BCATc inhibitor 2 ameliorated mitochondrial dysfunction and apoptosis in oleic acid-induced non-alcoholic fatty liver disease model.

Nonalcoholic fatty liver disease (NAFLD) is a prevalent hepatic disease in the world. Disorders of branched chain amino acid (BCAA) metabolism is involved in various diseases. In this study, we aim to explore the role of BCAA metabolism in the development of NAFLD and the protective effect of BCATc Inhibitor 2, an inhibitor of cytosolic branched chain amino acid transaminase, against NAFLD as well as its underlying mechanism. It was found that oleic acid induced lipid accumulation and apoptosis in HepG2 and LO2 cells. Supplementation of BCAAs further aggravated oleic acid-induced lipid accumulation and apoptosis. In contrast, treatment of BCATc Inhibitor 2 ameliorated oleic acid-induced lipid accumulation and apoptosis. Molecularly, supplementation of BCAAs or treatment of BCATc Inhibitor 2 up-regulated or down-regulated the expression of SREBP1 and lipogenesis-related genes without affecting lipolysis-related genes. BCATc Inhibitor 2 maintained mitochondrial function by ameliorating oleic acid-induced mitochondrial ROS generation and mitochondrial membrane potential disruption. In addition, BCATc Inhibitor 2 treatment alleviated oleic acid-induced activation of JNK and AKT signaling pathway and Bcl2/Bax/Caspase axis. In conclusion, our results indicate BCAA metabolism is involved in NAFLD and BCATc Inhibitor 2 protects against oleic acid-induced lipid accumulation and apoptosis. These findings suggest that BCATc Inhibitor 2 is a promising candidate drug for the treatment of NAFLD.

Metformin-induced AMPK activation promotes cisplatin resistance through PINK1/Parkin dependent mitophagy in gastric cancer.

Gastric cancer (GC) is one of the most common tumors worldwide, and cisplatin is a standard chemotherapeutic reagent for GC treatment. However, chemoresistance is an inherent challenge which limits its application and effectiveness in clinic. This study aims to investigate the mechanism of metformin-induced cisplatin resistance in GC. Intriguingly, the upregulation of mitophagy markers, mitochondrial fission, autophagy and mitophagosome were observed in SGC-7901/DDP cells compared to those in the SGC-7901 cells. Treatment with metformin significantly increased mitochondrial fission and mitophagy in both AGS and SGC-7901 cells, resulting in decreased ATP production, which unexpectedly protected GC cells against the cytotoxicity of cisplatin. In contrast, application of Chloroquine and 3-methyladenine, two inhibitors of autophagy, significantly alleviated the protective effect of metformin on SGC-7901 and AGS cells against cytotoxicity of cisplatin. Moreover, metformin also stimulated the phosphorylation of AMPK (Thr172) and increased the expression of mitophagy markers including Parkin and PINK1 in the AMPK signaling-dependent manner. Consistently, the cell viability and cell apoptosis assay showed that metformin-induced cisplatin resistance was prevented by knockdown of AMPKα1. Taken together, all data in this study indicate that metformin induced AMPK activation and PINK1/Parkin dependent mitophagy, which may contribute to the progression of cisplatin resistance in GC.

AMPK beta1 deletion reduces appetite, preventing obesity and hepatic insulin resistance.

The AMP-activated protein kinase (AMPK) is an alphabetagamma heterotrimer that regulates appetite and fuel metabolism. We have generated AMPK beta1(-/-) mice on a C57Bl/6 background that are viable, fertile, survived greater than 2 years, and display no visible brain developmental defects. These mice have a 90% reduction in hepatic AMPK activity due to loss of the catalytic alpha subunits, with modest reductions of activity detected in the hypothalamus and white adipose tissue and no change in skeletal muscle or heart. On a low fat or an obesity-inducing high fat diet, beta1(-/-) mice had reduced food intake, reduced adiposity, and reduced total body mass. Metabolic rate, physical activity, adipose tissue lipolysis, and lipogenesis were similar to wild type littermates. The reduced appetite and body mass of beta1(-/-) mice were associated with protection from high fat diet-induced hyperinsulinemia, hepatic steatosis, and insulin resistance. We demonstrate that the loss of beta1 reduces food intake and protects against the deleterious effects of an obesity-inducing diet.

Whole body deletion of AMP-activated protein kinase {beta}2 reduces muscle AMPK activity and exercise capacity.

AMP-activated protein kinase (AMPK) ß subunits (ß1 and ß2) provide scaffolds for binding α and γ subunits and contain a carbohydrate-binding module important for regulating enzyme activity. We generated C57Bl/6 mice with germline deletion of AMPK ß2 (ß2 KO) and examined AMPK expression and activity, exercise capacity, metabolic control during muscle contractions, aminoimidazole carboxamide ribonucleotide (AICAR) sensitivity, and susceptibility to obesity-induced insulin resistance. We find that ß2 KO mice are viable and breed normally. ß2 KO mice had a reduction in skeletal muscle AMPK α1 and α2 expression despite up-regulation of the ß1 isoform. Heart AMPK α2 expression was also reduced but this did not affect resting AMPK α1 or α2 activities. AMPK α1 and α2 activities were not changed in liver, fat, or hypothalamus. AICAR-stimulated glucose uptake but not fatty acid oxidation was impaired in ß2 KO mice. During treadmill running ß2 KO mice had reduced maximal and endurance exercise capacity, which was associated with lower muscle and heart AMPK activity and reduced levels of muscle and liver glycogen. Reductions in exercise capacity of ß2 KO mice were not due to lower muscle mitochondrial content or defects in contraction-stimulated glucose uptake or fatty acid oxidation. When challenged with a high-fat diet ß2 KO mice gained more weight and were more susceptible to the development of hyperinsulinemia and glucose intolerance. In summary these data show that deletion of AMPK ß2 reduces AMPK activity in skeletal muscle resulting in impaired exercise capacity and the worsening of diet-induced obesity and glucose intolerance.

Safety and immunogenicity of hepatitis E vaccine in elderly people older than 65 years.

BACKGROUND: Hepatitis E virus (HEV) infection is a leading cause of acute hepatitis worldwide, and results in high morbidity and mortality rates among elderly people in China. The hepatitis E vaccine, Hecolin®, has been shown to be safe and highly efficacious among healthy adults aged 16-65 years old. However, there is no data about Hecolin® vaccination in elderly people older than 65 years (y). METHODS: An open-labeled, controlled trial was conducted to evaluate the safety and immunogenicity of Hecolin® among the elderly aged >65 y. A total of 601 eligible participants were enrolled. Among them, 200 elderly people aged >65 y and 201 adults aged 18-65 y were assigned to the Hecolin® groups and vaccinated at day 0, month 1 and month 6. Serum samples were collected for anti-HEV IgG determination at day 0 prior to immunization and at month 7. The remaining 200 elderly people aged >65 y were assigned to the safety control group and received no intervention but were instructed to report any adverse events that occurred during the whole study period in the same way as those in the Hecolin® groups. RESULTS: After receiving 3 doses of Hecolin® with the standard schedule, most (96.7%) of the vaccinated elderly people aged >65 y seroconverted at one month after the final dose (month 7). At month 7, the geometric mean concentrations of anti-HEV IgG were 5.36 (95% CI, 3.88-7.41) and 19.65 (95% CI, 16.81-22.98) among the baseline seronegative and seropositive elderly, respectively. Of the vaccinated elderly, 97.3% (177/182) had anti-HEV IgG levels higher than 1.0 WU/ml at month 7. Hecolin® was very well tolerated in this population. No vaccine-related SAEs were reported. CONCLUSIONS: Hecolin® is immunogenic and well tolerated in elderly people aged greater than 65 years.