Omega-3 PUFAs slow organ aging through promoting energy metabolism.

Energy metabolism disorder, mainly exhibiting the inhibition of fatty acid degradation and lipid accumulation, is highly related with aging acceleration. However, the intervention measures are deficient. Here, we reported Omega-3 polyunsaturated fatty acids (Omega-3 PUFAs), especially EPA, exerted beneficial effects on maintaining energy metabolism and lipid homeostasis to slow organ aging. As the endogenous agonist of peroxisome proliferator-activated receptor α (PPARα), Omega-3 PUFAs significantly boosted fatty acid ß-oxidation and ATP production in multiple aged organs. Consequently, Omega-3 PUFAs effectively inhibited age-related pathological changes, preserved organ function, and retarded aging process. The beneficial effects of Omega-3 PUFAs were also testified in mfat-1 transgenic mice, which spontaneously generate abundant endogenous Omega-3 PUFAs. In conclusion, our study innovatively demonstrated Omega-3 PUFAs administration in diet slow aging through promoting energy metabolism. The supplement of Omega-3 PUFAs or fat-1 transgene provides a promising therapeutic approach to promote healthy aging in the elderly.

Adiponectin Suppresses Metastasis of Nasopharyngeal Carcinoma through Blocking the Activation of NF-κB and STAT3 Signaling.

Adiponectin is an adipocytokine with anti-inflammatory and anticancer properties. Our previous study has shown that blood adiponectin levels were inversely correlated to the risk of nasopharyngeal carcinoma (NPC), and that adiponectin could directly suppress the proliferation of NPC cells. However, the effect of adiponectin on NPC metastasis remains unknown. Here, we revealed in clinical studies that serum adiponectin level was inversely correlated with tumor stage, recurrence, and metastasis in NPC patients, and that low serum adiponectin level also correlates with poor metastasis-free survival. Coculture with recombinant adiponectin suppressed the migration and invasion of NPC cells as well as epithelial-mesenchymal transition (EMT). In addition, recombinant adiponectin dampened the activation of NF-κB and STAT3 signaling pathways induced by adipocyte-derived proinflammatory factors such as leptin, IL-6, and TNF-α. Pharmacological activation of adiponectin receptor through its specific agonist, AdipoRon, largely stalled the metastasis of NPC cells. Taken together, these findings demonstrated that adiponectin could not only regulate metabolism and inhibit cancer growth, but also suppress the metastasis of NPC. Pharmacological activation of adiponectin receptor may be a promising therapeutic strategy to stall NPC metastasis and extend patients' survival.

Endogenous production of n-3 polyunsaturated fatty acids protects mice from carbon tetrachloride-induced liver fibrosis by regulating mTOR and Bcl-2/Bax signalling pathways.

NEW FINDINGS: What is the central question of this study? What is the protective benefit of n-3 polyunsaturated fatty acids (PUFAs) on liver fibrosis and what are the relevant signalling pathways in a transgenic mouse model overexpressing the mfat-1 enzyme? What is the main finding and its importance? n-3 PUFA elevation strongly prevented carbon tetrachloride (CCl4 )-induced hepatic damage and inhibited the activation of hepatic stellate cells. n-3 PUFAs suppressed CCl4 -induced activation of mTOR, elevated Bcl-2 expression, and reduced Bax level, suggesting that n-3 PUFAs can render strong protective effects against liver fibrosis and point to the potential of mfat-1 gene therapy as a treatment modality. ABSTRACT: Liver fibrosis is a reversible wound healing response with excessive accumulation of extracellular matrix proteins. It is a globally prevalent disease with ultimately severe pathological consequences. However, very few current clinical therapeutic options are available. Nutritional addition of n-3 polyunsaturated fatty acids (PUFAs) can delay and lessen the development of liver fibrosis. Herein, this study examined the protective benefit of n-3 PUFAs on liver fibrosis and the relevant signalling pathways using a transgenic mouse model overexpressing the mfat-1 enzyme that converts n-6 to n-3 PUFAs. Male C57BL/6 wild-type and mfat-1 transgenic mice were administered carbon tetrachloride (CCl4 ) or control corn oil by intraperitoneal injection. Blood alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were subsequently measured. CCl4 -induced hepatic damage and fibrosis were assessed using haematoxylin-eosin and Masson's trichrome staining. Western blot assays were used to detect and quantify fibrosis-related proteins and mechanistic target of rapamycin (mTOR) and B-cell lymphoma 2 (Bcl-2)/Bcl-2-associated X protein (Bax) signalling components. The direct effect of docosahexaenoic acid (DHA) on primary hepatic stellate cells (HSCs) was also investigated in a co-culture experiment. n-3 PUFAs, as a result of mfat-1 activity, had a strong protective effect on liver fibrosis. The elevation of ALT and AST induced by CCl4 was significantly lessened in the mfat-1 mice. Histological determination revealed the protective effects of n-3 PUFAs on liver inflammation and collagen deposition. Co-incubation with DHA reduced the expression of profibrogenic factors in the primary HSCs. Moreover, mfat-1 transgenic mice showed significant reduction of proteins that are involved in mTOR and Bcl-2/Bax signalling pathways. Collectively, these results suggest that n-3 PUFA elevation strongly prevents CCl4 -induced hepatic damage by directly inhibiting the activation of HSCs and regulating the basal activity of the mTOR and Bcl-2/Bax signalling pathways. Gene therapy applying mfat-1 and elevating n-3 PUFAs represents a promising treatment strategy to prevent liver fibrosis.

Salubrinal, a novel inhibitor of eIF-2α dephosphorylation, promotes erythropoiesis at early stage targeted by ufmylation pathway.

Ufmylation was proved to play a crucial role in hematopoietic stem cell (HSC) survival and erythroid differentiation, ufmylation deficiency induces acute anemia and lethality of embryos and adults in mouse models. To screen some compounds to rescue phenotypes induced by gene deletion, in this study, we used DDRGK1F/F ; CreERT2 conditional knockout mice, DDRGK1F/F ; CreERT2 bone marrow (BM) and fetal liver cells (FL), Uba5, and DDRGK1 knockdown human CD34 cell in vivo and in vitro, we found salubrinal, a novel inhibitor of eIF-2α dephosphorylation, promoted erythropoiesis at early stage, and partly rescued the acute anemia induce by DDRGK1 deficiency through upregulation of ufmylation and erythroid transcription factors. In phenylhydrazine (PHZ)-induced hemolytic anemia mice, interestingly, salubrinal could significantly improve hemocrit and red blood cell (RBC) indices of the mice treated with PHZ via upregulation of ufmylation. Its novel function was verified to attenuate unfolded protein response (UPR) and cell death programs, and to keep endoplasmic reticulum (ER) homeostasis in HSCs. Taken together results, it suggested that salubrinal may be a promising antianemic agent targeted by ufmylation.

FKBP38 deletion exacerbates ConA-induced hepatitis by promoting the immune response through the MCP-1/p38 pathway.

Autoimmune hepatitis (AIH) is a chronic liver disease characterized by immune dysregulation and hepatocyte damage. FKBP38, a member of the immunophilin family, has been implicated in immune regulation and the modulation of intracellular signaling pathways; however, its role in AIH pathogenesis remains poorly understood. In this study, we aimed to investigate the effects of hepatic FKBP38 deletion on AIH using a hepatic FKBP38 knockout (LKO) mouse model created via cre-loxP technology. We compared the survival rates, incidence, and severity of AIH in LKO mice with those in control mice. Our findings revealed that hepatic FKBP38 deletion resulted in an unfavorable prognosis in LKO mice with AIH. Specifically, LKO mice exhibited heightened liver inflammation and extensive hepatocyte damage compared to control mice, with a significant decrease in anti-apoptotic proteins and a marked increase in pro-apoptotic proteins. Additionally, transcriptional and translational levels of pro-inflammatory cytokines and chemokines were significantly increased in LKO mice compared to control mice. Immunoblot analysis showed that MCP-1 expression was significantly elevated in LKO mice. Furthermore, the phosphorylation of p38 was increased in LKO mice with AIH, indicating that FKBP38 deletion promotes liver injury in AIH by upregulating p38 phosphorylation and increasing MCP-1 expression. Immune cell profiling demonstrated elevated populations of T, NK, and B cells, suggesting a dysregulated immune response in LKO mice with AIH. Overall, our findings suggest that FKBP38 disruption exacerbates AIH severity by augmenting the immune response by activating the MCP-1/p38 signaling pathway.

[Protective Effect of Endogenous ω-3 Polyunsaturated Fatty Acid Against Cisplatin Induced Myelosuppression].

OBJECTIVE: To investigate the protective effect of endogenous ω-3 polyunsaturated fatty acid (PUFA) against cisplatin-induced myelosuppression and the mechanism of reducing apoptosis in bone marrow nucleated cells using mfat-1 transgenic mice. METHODS: The experimental animals were divided into 4 groups: wild-type mice normal control group, mfat-1 transgenic mice normal control group, wild-type mice model group and mfat-1 transgenic mice model group. The mice in the model group were injected intraperitoneally with 7.5 mg/kg cisplatin on day 0 and day 7 to construct a myelosuppression model, while the mice in the normal control group were injected intraperitoneally with an equal amount of saline, and their status was observed and their body weight was measured daily. Peripheral blood was taken after 14 day for routine blood analysis, and the content and proportion of PUFA in peripheral blood were detected using gas chromatography. Bone marrow nucleated cells in the femur of mice were counted. The histopathological changes in bone marrow were observed by histopathological staining. The apoptosis of nucleated cells and the expression level changes of apoptosis-related genes in the bone marrow of mice were detected by flow cytometry and fluorescence quantitative PCR. RESULTS: Compared with wild-type mice, mfat-1 transgenic mice showed significantly increased levels of ω-3 PUFA in peripheral blood and greater tolerance to cisplatin. Peripheral blood analysis showed that endogenous ω-3 PUFA promoted the recovery of leukocytes, erythrocytes, platelets and haemoglobin in peripheral blood of myelosuppressed mice. The results of HE staining showed that endogenous ω-3 PUFA significantly improved the structural damage of bone marrow tissue induced by cisplatin. Flow cytometry and PCR showed that, compared with wild-type mice model group, the apoptosis rate of bone marrow nucleated cells in mfat-1 transgenic mice was significantly reduced ( P < 0.001), and the expression of anti-apoptotic genes Bcl-2 mRNA was significantly increased ( P < 0.01), while the expressions of pro-apoptotic genes Bax and Bak mRNA were significantly reduced ( P < 0.001, P < 0.05). CONCLUSION: Endogenous ω-3 PUFA can reduce cisplatin-induced apoptosis in bone marrow nucleated cells, increase the number of peripheral blood cells and exert a protective effect against cisplatin-induced myelosuppression by regulating the expression of apoptosis-related genes.

Eicosapentaenoic acid metabolites promotes the trans-differentiation of pancreatic α cells to ß cells.

Type 1 diabetes mellitus (T1DM) is characterized by life-threatening absolute insulin deficiency. Although ω-3 polyunsaturated fatty acids (PUFAs) displayed significant anti-hyperglycemic activity, the insulinotropic effects of their metabolites remain unknown. In this study, we took advantage of a transgenic model, mfat-1, that overexpresses an ω-3 desaturase and can convert ω-6 PUFAs to ω-3 PUFAs. Eicosapentaenoic acid (EPA) was sharply elevated in the pancreatic tissues of mfat-1 transgenic mice compared with wild-type (WT) mice. In contrast to the WT mice, the mfat-1 transgenics did not develop overt diabetes and still maintained normal blood glucose levels and insulin secretion following streptozotocin-treatment. Furthermore, under the condition of pancreatic ß-cell damage, co-incubation of the metabolites of EPA produced from the CYP 450 pathway with isolated islets promoted the overexpression of insulin as well as ß-cell specific markers, pdx1 and Nkx6.1 in pancreatic α-cells. Addition of EPA metabolites to the cultured glucagon-positive α-cell lines, a series of pancreatic ß-cell markers were also found significantly elevated. Combined together, these results demonstrated the effects of ω-3 PUFAs and their metabolites on the trans-differentiation from α-cells to ß-cells and its potential usage in the intervention of T1DM.

Endogenous production of ω-3 polyunsaturated fatty acids mitigates cisplatin-induced myelosuppression by regulating NRF2-MDM2-p53 signaling pathway.

Cisplatin is a chemotherapy medication used to treat a wide range of cancers. A common side effect of cisplatin is myelosuppression. Research suggests that oxidative damages are strongly and consistently related to myelosuppression during cisplatin treatment. ω-3 polyunsaturated fatty acids (PUFAs) can enhance the antioxidant capacity of cells. Herein, we investigated the protective benefit of endogenous ω-3 PUFAs on cisplatin-induced myelosuppression and the underlying signaling pathways using a transgenic mfat-1 mouse model. The expression of mfat-1 gene can increase endogenous levels of ω-3 PUFAs by enzymatically converting ω-6 PUFAs. Cisplatin treatment reduced peripheral blood cells and bone marrow nucleated cells, induced DNA damage, increased the production of reactive oxygen species, and activated p53-mediated apoptosis in bone marrow (BM) cells of wild-type mice. In the transgenics, the elevated tissue ω-3 PUFAs rendered a robust preventative effect on these cisplatin-induced damages. Importantly, we identified that the activation of NRF2 by ω-3 PUFAs could trigger an antioxidant response and inhibit p53-mediated apoptosis by increasing the expression of MDM2 in BM cells. Thus, endogenous ω-3 PUFAs enrichment can strongly prevent cisplatin-induced myelosuppression by inhibiting oxidative damage and regulating the NRF2-MDM2-p53 signaling pathway. Elevation of tissue ω-3 PUFAs may represent a promising treatment strategy to prevent the side effects of cisplatin.

Transcriptome profiling reveals the role of ZBTB38 knock-down in human neuroblastoma.

ZBTB38 belongs to the zinc finger protein family and contains the typical BTB domains. As a transcription factor, ZBTB38 is involved in cell regulation, proliferation and apoptosis, whereas, functional deficiency of ZBTB38 induces the human neuroblastoma (NB) cell death potentially. To have some insight into the role of ZBTB38 in NB development, high throughput RNA sequencing was performed using the human NB cell line SH-SY5Y with the deletion of ZBTB38. In the present study, 2,438 differentially expressed genes (DEGs) in ZBTB38-/- SH-SY5Y cells were obtained, 83.5% of which was down-regulated. Functional annotation of the DEGs in the Kyoto Encyclopedia of Genes and Genomes database revealed that most of the identified genes were enriched in the neurotrophin TRK receptor signaling pathway, including PI3K/Akt and MAPK signaling pathway. we also observed that ZBTB38 affects expression of CDK4/6, Cyclin E, MDM2, ATM, ATR, PTEN, Gadd45, and PIGs in the p53 signaling pathway. In addition, ZBTB38 knockdown significantly suppresses the expression of autophagy-related key genes including PIK3C2A and RB1CC1. The present meeting provides evidence to molecular mechanism of ZBTB38 modulating NB development and targeted anti-tumor therapies.

A potential role for SMAD9 in goose follicular selection through regulation of mRNA levels of luteinizing hormone receptor.

The egg production of poultry depends on follicular development and selection. Nonetheless, the mechanism underlying the priority of selecting of hierarchical follicles is completely unknown. SMAD9 is one of the important transcription factors in the BMP/SMAD pathway and is involved in goose follicular initiation. To identify its potential role in determination of the goose follicle hierarchy, we used BMP type I receptor inhibitor LDN-193189 both in vivo and in vitro and found that SMAD9 mRNA expression decreased in the presence of LDN-193189. While the level of SMAD9 mRNA decreased after treatment with LDN-193189, we found that the egg production (7.08 eggs per bird per year) of the animals increased, estradiol (E2) levels significantly increased, but the levels of progesterone (P4) remained unchanged. We also detected a significant increase in luteinizing hormone receptor (LHR) mRNA expression, but no change in follicle-stimulating hormone receptor (FSHR) mRNA amounts. The in vitro experimental results indicated that SMAD9 knockdown by RNA interference noticeably reduced E2 and P4 biosynthesis and FSHR and LHR mRNA expression in goose granulosa cells. Chromatin immunoprecipitation assay of goose granulosa cells revealed that phospho-SMAD9 bound to the LHR promoter and possibly regulated its transcriptional activity. These findings revealed that SMAD9 is differentially expressed in goose follicles, and acts as a key player in the control over goose follicular selection.

The effects of mouse ovarian granulosa cell function and related gene expression by suppressing BMP/Smad signaling pathway.

BMP I type receptor inhibitor can selectively inhibit BMP/Smad signaling pathways, mainly by inhibiting the BMP I type receptor activity to prevent phosphorylation of Smad1, Smad5 and Smad9. The aim of the present study was to explore the effects of mouse ovarian granulosa cell function and related gene expression by suppressing BMP/Smad signaling pathway with LDN-193189(A type of BMP I type receptor inhibitor). In this study, we cultivate the original generation of mouse ovarian granular cells then collect cells and cell culture medium after treatment. Cellular localization and expression of Smad9 and P-smad9 proteins was studied by immunofluorescence (IF) in the ovarian granulosa cells of mouse; Related genes mRNA and proteins expression was checked by QRT-PCR and Western blot; Detected the concentration of related hormones by using ELISA kit; finally, the growth of the cells was analyzed by plotting cell growth curve with CCK-8 assay. The results indicate that, suppression of BMP/Smad signaling pathway can inhibit the expression of LHR and FSHR, inhibit cell proliferation and decrease E2 secretion, the mechanism of action maybe reduce the expression of smad9, at the same time, we found that the feedback regulation of smad9 may affect the expression of FSHR and cell proliferation.

ZBTB38, a novel regulator of autophagy initiation targeted by RB1CC1/FIP200 in spinal cord injury.

Apoptosis is an important contributing factor in spinal cord injury (SCI). ZBTB38 is involved in the transcriptional regulation of multiple signaling pathways, is differentially expressed at different SCI stages, and may provide a therapeutic strategy for the treatment of patients with SCI. In this study, we found that autophagy is blocked in ZBTB38 knockdown SH-SY5Y cells and that the expression levels of LC3B II/I decreased and P62 increased. We used transcriptome high-throughput sequencing to identify the target in ZBTB38 knockdown cells. From the transcriptome profile, RB1CC1 (i.e., FIP200), a key component of the initiation machinery of autophagy (FIP200-ATG13-ULK1-ATG101), was found to decrease 4.2-fold following ZBTB38 knockdown. When RB1CC1-overexpressed plasmids were transfected into ZBTB38 knockdown cells, they rescued the phenotype of ZBTB38 knockdown cells. Cell proliferation and viability were significantly enhanced by RB1CC1 overexpression, and LC3B and P62 expression returned to their original levels. We also injected ZBTB38-overexpressed lentivirus into the injured center of the spinal cord and detected significant upregulation of RB1CC1 in the spinal cord. ZBTB38 overexpression can promote autophagy and partly rescue the secondary damage of SCI. Therefore, our findings provide a new strategy for the treatment of SCI.

Repair of bone defect of the lateral forefoot by double segment triangular fibula flap with vascular pedicle: A case report.

Objective: To expound the clinical effect of a new operation by transplanting double segment triangular fibula flap with vascular pedicle to repair the forefoot with lateral bone defect, and to study how to improve the operation method in the following stage. Methods: The inclusion criteria: More than 2 phalangeal and metatarsal bones defects of the lateral forefoot, widespread skin and soft tissue defects on pelma and dorsal foot, and destruction of the anterior aspect of foot arch, which seriously affects the foot function. There was one case of clinical application in November 2014. The repairing method is as followed: the harvested vascularized free fibula was cut into 2 segments and then they were folded into a right angle. According to selected control points on the residual metatarsals, an optimal stereo triangular net was constructed. Meanwhile, according to flow-through mode, the free anterolateral thigh flap was incorporated to repair the forefoot and foot arch. Results: Postoperative bone flaps all survived. After a 17-month following up, it was found that the grafted fibular healed well, shape of the foot was good, weight-bearing walking was practical, a slight limp and discomfort with plantar pain existed, sensory recovery reached S3 level and functional recovery of weight-bearing walking by forefoot reached W3 level, comprehensive evaluation was good, and there were wear scar and ulcer on the plantar flap during long-time walking for patients, such results were excellent according to foot function scoring criteria. Conclusion: In this operation the grafted fibula was fold into a triangle according to actual need, which though not completely restores the tridimensional structure of the longitudinal, transverse arches of the lateral foot makes weight-bearing walking possible, besides, its appearance and function is satisfactory. Such an operation has overcome the shortage of non-tridimensional structure of the transverse arch etc. in traditional operations and it should be an ideal operation in repairing serious defects on the lateral forefoot through further improvement.