Bibliometric and visualized analysis of hydrogels in organoids research.

Over the past decades, there has been ongoing effort to develop complex biomimetic tissue engineering strategies for in vitro cultivation and maintenance of organoids. The defined hydrogels can create organoid models for various organs by changing their properties and various active molecules. An increasing number of researches has been done on the application of hydrogels in organoids, and a large number of articles have been published on the topic. Although there have been existing reviews describing the application of hydrogels in the field of organoids, there is still a lack of comprehensive studies summarizing and analyzing the overall research trends in this field. The citation can be used as an indicator of the scientific influence of an article in its field. This study aims to evaluate the application of hydrogels in organoids through bibliometric analysis, and to predict the hotspots and developing trends in this field.

Characteristics of Metabolites in the Development of Atherosclerosis in Tibetan Minipigs Determined Using Untargeted Metabolomics.

BACKGROUND: Atherosclerosis (AS) is a chronic progressive disease caused by lipometabolic disorder. However, the pathological characteristics and mechanism of AS have not been fully clarified. Through high-fat and high-cholesterol diet induction, Tibetan minipigs can be used as the AS model animals, as they have a very similar AS pathogenesis to humans. METHODS: In this study, we built an AS model of Tibetan minipigs and identified the differential abundance metabolites in the development of AS based on untargeted metabolomics. RESULTS: We found that sphingolipid metabolism and glucose oxidation were obviously higher in the AS group and phenylalanine metabolism was reduced in the AS group. Moreover, in the development of AS, gluconolactone was enriched in the late stage of AS whereas biopterin was enriched in the early stage of AS. CONCLUSIONS: Our research provides novel clues to investigate the metabolic mechanism of AS from the perspective of metabolomics.

Iron regulates chondrocyte phenotype in haemophilic cartilage through the PTEN/PI3 K/AKT/FOXO1 pathway.

OBJECTIVE: Our previous study demonstrated that iron overload could lead to haemophilic cartilage destruction by changing chondrocyte phenotype. This change was caused by iron's effect on chondrocyte expression of FGF23 and SOX9, in addition to iron-induced chondrocyte apoptosis and cartilage extracellular matrix degradation. However, the underlying mechanisms remain unclear. This study aimed to determine the mechanism by which iron influences chondrocyte phenotype in the pathogenesis of haemophilic cartilage destruction. METHODS: The expression of the PTEN/PI3K/AKT/FOXO1 signal pathway in the articular cartilage of patients with haemophilic arthritis (HA) or osteoarthritis (OA) was determined using western blot (WB). Additionally, we quantified the expression of iron-induced PTEN, PI3K, p-PI3K, AKT, p-AKT, FOXO1, and p-FOXO1 in primary human normal chondrocyte cells (HUM-iCell-s018) using WB. RESULTS: We found that compared to that in patients with OA, the expression of PTEN, PI3K, AKT, and FOXO1 in the articular cartilage of patients with HA was up-regulated, while the expression of p-PI3K, p-AKT, and p-FOXO1 was down-regulated. Additionally, iron increased the expression of PTEN, PI3K, AKT, and FOXO1 and suppressed that of p-PI3K, p-AKT, and p-FOXO1 in chondrocytes in a dose-dependent manner. CONCLUSIONS: Our findings demonstrated that iron was involved in the pathogenesis of haemophilic cartilage destruction by affecting chondrocyte phenotype through the inhibition of the PTEN/PI3K/AKT/FOXO1 pathway.

IL-6, IL-1ß and TNF-α regulation of the chondrocyte phenotype: a possible mechanism of haemophilic cartilage destruction.

OBJECTIVE: Proinflammatory cytokines are considered to be one of the key causes of haemophilic cartilage destruction by inducing chondrocyte apoptosis and extracellular matrix degradation. However, few studies have focused on how proinflammatory cytokines regulate the phenotypic changes of chondrocytes, which may be an important factor in haemophilic cartilage degradation pathogenesis. More understanding is needed about the effect of proinflammatory cytokines on phenotypic changes of the chondrocyte. The objective of this study was to examine how IL-6, TNF-α and IL-1ß regulate the chondrocyte phenotype, which may be an important factor in haemophilic cartilage degradation pathogenesis. METHODS: HUM-iCell-s018 chondrocytes were treated with increasing concentrations of TNF-α, IL-6 or IL-1ß (0, 1, 5, 10 ng/ml) for 24 h, then FGF23 and SOX9 expression was determined by qRT-PCR and WB, respectively. RESULTS: We found that TNF-α, IL-6 and IL-1ß induced FGF23 and suppressed SOX9 expression in chondrocytes in a dose-dependent manner. IL-1ß had a stronger regulatory effect on FGF23, while TNF-α and IL-6 had stronger regulatory effects on SOX9. CONCLUSIONS: These findings suggest that IL-6, IL-1ß and TNF-α may be involved in haemophilic cartilage destruction pathogenesis by altering the chondrocyte phenotype through modulation of FGF23 and SOX9 gene expression.

Identification of six hub genes and two key pathways in two rat renal fibrosis models based on bioinformatics and RNA-seq transcriptome analyses.

Renal fibrosis (RF) is the common pathological manifestation and central treatment target of multiple chronic kidney diseases with high morbidity and mortality. Currently, the molecular mechanisms underlying RF remain poorly understood, and exploration of RF-related hub targets and pathways is urgently needed. In this study, two classical RF rat models (adenine and UUO) were established and evaluated by HE, Masson and immunohistochemical staining. To clear molecular mechanisms of RF, differentially expressed genes (DEGs) were identified using RNA-Seq analysis, hub targets and pathways were screened by bioinformatics (functional enrichment analyses, PPI network, and co-expression analysis), the screening results were verified by qRT-PCR, and potential drugs of RF were predicted by network pharmacology and molecular docking. The results illustrated that renal structures were severely damaged and fibrotic in adenine- and UUO-induced models, as evidenced by collagen deposition, enhanced expressions of biomarkers (TGF-ß1 and α-SMA), reduction of E-cadherin biomarker, and severe renal function changes (significantly decreased UTP, CREA, Ccr, and ALB levels and increased UUN and BUN levels), etc. 1189 and 1253 RF-related DEGs were screened in the adenine and UUO models, respectively. Two key pathways (AGE-RAGE and NOD-like receptor) and their hub targets (Tgfb1, Col1a1, Nlrc4, Casp4, Trpm2, and Il18) were identified by PPI networks, co-expressed relationships, and qRT-PCR verification. Furthermore, various reported herbal ingredients (curcumin, resveratrol, honokiol, etc.) were considered as important drug candidates due to the strong binding affinity with these hub targets. Overall, this study mainly identified two key RF-related pathways (AGE-RAGE and NOD-like receptor), screened hub targets (Tgfb1, Col1a1, Nlrc4, Casp4, Trpm2, and Il18) that involved inflammation, ECM formation, myofibroblasts generation, and pyroptosis, etc., and provided referable drug candidates (curcumin, resveratrol, honokiol, etc.) in basic research and clinical treatment of RF.

[Expression of Sirtuin 1 in visceral adipose tissue in Tibetan mini-pigs with obesity and insulin resistance induced by high fat/cholesterol diet].

OBJECTIVE: To investigate the role of Sirt1 in visceral adipose tissue in Tibetan mini-pigs with obesity and insulin resistance induced by high fat/cholesterol diet. METHODS: Twelve male Tibetan mini-pigs were divided into 2 groups randomly: normal control (NC) group, high-fat/cholesterol (HFC) diet group, 6 in each group. After 16 weeks of modeling, fasting body weight and body mass index (BMI) were measured. Total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) were measured in anterior venous blood, and atherosclerosis index (AI) was calculated. Meanwhile, intravenous glucose tolerance test was conducted to observe the changes of blood glucose and insulin, and the area under the curve (AUC) was calculated. After euthanasia, visceral fat rate was detected, and visceral fat tissue was taken for histopathological observation and fat cell diameter analysis. RT-PCR was used to observe the mRNA expression levels of Sirtuin1 (Sirt1), insulin-like growth factor-1 (IGF-1), glucose transporter 4 (GLUT4), peroxisome proliferator-activated receptor γ (PPARγ), peroxisome proliferator-activated receptor γ-assisted activator 1α (PGC-1α), forkhead box protein O1 (FoxO1), lipolysis-related gene hormone-sensitive lipase (HSL), and fat synthesis-related gene fatty acid synthase (FASN)changes in adipose tissue. RESULTS: Compared with the NC group, the body weight, BMI, TC, LDL-C, HDL-C, AI and visceral fat rate were significantly increased after 16 weeks of high-fat/cholesterol induction in Tibetan mini-pigs(P＜0.05,P＜0.01). Meanwhile, the glucose tolerance curve was significantly delayed and the area under the curve of blood glucose and insulin was significantly increased (P＜0.05). HE pathological observation and quantitative analysis showed that fat cells were hypertrophy and the average cell diameter was increased significantly (P＜0.01). In addition, the mRNA expression levels of Sirt1,PGC-1α, GLUT4, and HSL were all decreased in varying degrees in adipose tissue, among which the mRNA expressions of Sirt1 and HSL were significantly decreased (P＜0.05), while the mRNA expressions of FOXO1, IGF-1, PPARγ, and FASN were significantly increased (P＜0.05, P＜0.01). CONCLUSION: Tibetan mini-pigs were induced by high fat/cholesterol diet to form obesity model with phenotypic characteristics such as lipid disorder and insulin resistance, whereas Sirt1 plays a key role in visceral fat deposition and insulin sensitivity reduction in obese Tibetan mini-pigs.

Transcriptome profiling reveals multiple pathways responsible for the beneficial metabolic effects of Smilax glabra flavonoids in mouse 3T3-L1 adipocytes.

Smilax glabra Roxb. (SG) is a well-known traditional Chinese medicine that has been extensively used as both food and folk medicine in many countries. Although many beneficial health effects of SG and its primary components have been reported, their action on adipocyte function remains unknown. In the present study, we investigated the effects of the total flavonoids from Smilax glabra Roxb. (SGF) on lipid accumulation in mouse 3T3-L1 adipocytes and further elucidated its potential mechanism using RNA-Seq transcriptome technique. Our results showed that SGF exposure significantly decreased the lipid droplet size and the levels of cellular free fatty acids, while triglyceride accumulation was not affected by SGF. Transcriptome analysis revealed that SGF induced the expression of genes involved in triglyceride storage, fatty acid ß-oxidation and mitochondrial biogenesis. Furthermore, we also observed an increased cellular ATP level and mitochondrial mass after SGF exposure, indicating that SGF enhanced mitochondrial function. The other relevant transcriptional changes appeared to be involved in AMPK/PGC-1α signaling, inflammatory response, as well as PI3K/AKT and calcium signaling pathways, which might contribute to the beneficial metabolic effects of SGF on adipocyte function. The results of Western blotting confirmed that SGF could increase the phosphorylation of AMPK while decrease the phosphorylation of AKT in adipocytes. Altogether, our results provided novel information about the molecular mechanism responsible for the effects of SGF on fat storage in adipocytes and highlights the potential metabolic benefits of SGF on human obesity and its related chronic diseases.

Correction to: Transcriptomic analysis of hepatic responses to testosterone deficiency in miniature pigs fed a high-cholesterol diet.

Following the publication of the original article [1], it was reported that the accession number given in the 'Data accessibility' declaration, GSE65696, is incorrect.

Royal Jelly Ameliorates Behavioral Deficits, Cholinergic System Deficiency, and Autonomic Nervous Dysfunction in Ovariectomized Cholesterol-Fed Rabbits.

Estrogen deficiency after menopause is associated with autonomic nervous changes, leading to memory impairment and increased susceptibility to Alzheimer's disease (AD). Royal jelly (RJ) from honeybees (Apis mellifera) has estrogenic activity. Here, we investigated whether RJ can improve behavior, cholinergic and autonomic nervous function in ovariectomized (OVX) cholesterol-fed rabbits. OVX rabbits on high-cholesterol diet were administered with RJ for 12 weeks. The results showed that RJ could significantly improve the behavioral deficits of OVX cholesterol-fed rabbits and image structure of the brain. RJ reduced body weight, blood lipid, as well as the levels of amyloid-beta (Aß), acetylcholinesterase (AchE), and malonaldehyde (MDA) in the brain. Moreover, RJ also increased the activities of choline acetyltransferase (ChAT) and superoxide dismutase (SOD) in the brain, and enhanced heart rate variability (HRV) and Baroreflex sensitivity (BRS) in OVX cholesterol-fed rabbits. Furthermore, RJ was also shown to reduce the content of Evans blue and the expression levels of Aß, beta-site APP cleaving enzyme 1(BACE1), and receptor for advanced glycation end products (RAGE), and increase the expression level of LDL(low density lipoprotein) receptor-related protein 1 (LRP-1) in the brain. Our findings suggested that RJ has beneficial effects in neurological disorders of postmenopausal women, which were associated with reducing cholesterol and Aß deposition, enhancing the estrogen levels and the activities of cholinergic and antioxidant systems, and ameliorating the blood⁻brain barrier (BBB) permeability and restoring autonomic nervous system.

Lower cardiovagal tone and baroreflex sensitivity associated with hepatic insulin resistance and promote cardiovascular disorders in Tibetan minipigs induced by a high fat and high cholesterol diet.

AIMS: A long-term high-fat/cholesterol (HFC) diet leads to hepatic insulin resistance (IR), which is associated with autonomic dysfunction and cardiovascular diseases risk increasing. However, whether this occurs in Tibetan minipigs remains unknown. We tested that a long-term HFC diet caused hepatic IR and promote cardiovascular disorders in Tibetan minipigs, and are associated with the reduction of cardiovagal tone and baroreflex sensitivity (BRS). METHODS: Male Tibetan minipigs were fed either a standard diet or a HFC diet, and were euthanized at 12 weeks. Thereafter, the minipigs were tested for biochemical blood indices, glucose tolerance, blood pressure, heart rate variability (HRV), BRS, and insulin receptor substrate (IRS)-associated gene and protein expression levels, as well as cardiac function. RESULTS: HFC-fed minipigs developed IR by increasing body weight, total cholesterol, fasting blood glucose and insulin levels, and nonesterified fatty acid (NEFA) and high sensitive C-reactive protein (hs-CRP) levels, glucose intolerance. Increased adipose cell size, hepatic fat deposition, malondialdehyde (MDA) content and NEFA level, down-regulation of IRS1, IRS2, PI3K, Akt, p-Akt, Glut2 and PGC1ɑ expression concomitant with up-regulation of mTOR, GSK3ß, TNF-ɑ, FOXO1, p-mTOR and p-p70S6K expression in the liver tissue, as well as hypertension and left ventricular diastolic dysfunction were observed in HFC-fed minipigs. HRV parameters and BRS values were further significantly reduced. Furthermore, multiple linear regression analysis showed that the development of hepatic IR toward cardiovascular disease was associated with low HFnu, RMSSD, BRS and LV -dp/dtmax, high NEFA, high hepatic TG content. CONCLUSION: These data suggest that HFC-fed Tibetan minipigs develop hepatic IR and promote cardiovascular disorders, and are associated with lower cardiovagal tone and BRS.

Royal Jelly Reduces Cholesterol Levels, Ameliorates Aß Pathology and Enhances Neuronal Metabolic Activities in a Rabbit Model of Alzheimer's Disease.

Alzheimer's disease (AD) is the most common form of dementia characterized by aggregation of amyloid ß (Aß) and neuronal loss. One of the risk factors for AD is high cholesterol levels, which are known to promote Aß deposition. Previous studies have shown that royal jelly (RJ), a product of worker bees, has potential neuroprotective effects and can attenuate Aß toxicity. However, little is known about how RJ regulates Aß formation and its effects on cholesterol levels and neuronal metabolic activities. Here, we investigated whether RJ can reduce cholesterol levels, regulate Aß levels and enhance neuronal metabolic activities in an AD rabbit model induced by 2% cholesterol diet plus copper drinking water. Our results suggest that RJ significantly reduced the levels of plasma total cholesterol (TC) and low density lipoprotein-cholesterol (LDL-C), and decreased the level of Aß in rabbit brains. RJ was also shown to markedly ameliorate amyloid deposition in AD rabbits from Aß immunohistochemistry and thioflavin-T staining. Furthermore, our study suggests that RJ can reduce the expression levels of ß-site APP cleaving enzyme-1 (BACE1) and receptor for advanced glycation end products (RAGE), and increase the expression levels of low density lipoprotein receptor-related protein 1 (LRP-1) and insulin degrading enzyme (IDE). In addition, we found that RJ remarkably increased the number of neurons, enhanced antioxidant capacities, inhibited activated-capase-3 protein expression, and enhanced neuronal metabolic activities by increasing N-acetyl aspartate (NAA) and glutamate and by reducing choline and myo-inositol in AD rabbits. Taken together, our data demonstrated that RJ could reduce cholesterol levels, regulate Aß levels and enhance neuronal metabolic activities in AD rabbits, providing preclinical evidence that RJ treatment has the potential to protect neurons and prevent AD.

Reproductive Hormones and Their Receptors May Affect Lung Cancer.

BACKGROUND/AIMS: In contrast to men, women have experienced a rapid increase in lung cancer mortality. Numerous studies have found that the sex differences in lung cancer are due to reproductive hormones. Experiments in female mice with and without ovariectomy were performed to explore the possible mechanism by which sex hormones (and their receptors) influence lung cancer. METHODS: Twenty-four female C57BL/6 mice aged 56-62 days were randomly divided into the ovariectomized group and the control group. In the ovariectomized group, the bilateral ovaries were removed via the dorsal approach, while the control group underwent a sham operation with bilateral ovarian fat resection at the same sites. After 3 weeks of recovery, Lewis lung cancer cells were transplanted into these mice by subcutaneous inoculation of a tumour cell suspension to establish the ovariectomized lung cancer model. Beginning on the 6th day after subcutaneous inoculation, mouse weight and transplanted tumour volume were measured every 3 days. After 3 weeks, all the mice were killed by cervical dislocation, and we measured the tumour weight. Mouse serum and tumour tissues were removed. Then, the serum levels of E2 (oestradiol) and T (testosterone) were detected by ELISA; the protein expression levels of AR (androgen receptor), ERα (oestrogen receptor α) and ERß (oestrogen receptor ß) were detected by Western Blot and IHC (immunohistochemistry); and the mRNA expression levels of AR, ERα and ERß were detected by qRT-PCR (quantitative real-time polymerase chain reaction) in the ovariectomized and control groups. RESULTS: Compared with the control group, both mouse weight and transplanted tumour volume increased rapidly in the ovariectomized group, and the transplanted tumour weight was significantly heavier in the ovariectomized group (1.83±0.40 and 3.13±0.43, P<0.05). E2 and T serum levels decreased exponentially in the ovariectomized group, while the E2/T ratio increased compared with the control group (E2: 55.88±11.45 and 78.21±9.37; T: 0.82±0.14 and 1.46±0.16; ratio: 69.62±14.43±29.81 and 52.22±5.42; all P<0.05). The Western blot and IHC results indicated that AR, ERα and ERß protein expression levels were obviously higher in transplanted tumour and lung tissues from the ovariectomized group, with particular increases in ERß in transplanted tumour tissue and in ERα in lung tissue. The PCR results also showed markedly higher mRNA expression levels of AR, ERα and ERß in the ovariectomized group, and in particular, ERß in transplanted tumour tissue and ERα in lung tissue were significantly increased in the ovariectomized group. CONCLUSION: Ovariectomy decreased E2 and T serum levels and increased the E2/T ratio in mice, and this imbalance in the internal environment promoted the growth of transplanted tumours. Sex hormone disorder not only promoted transplanted tumour growth but also significantly reduced the protein and mRNA expression levels of sex hormone receptors. The metabolism of E2 and T may affect the growth, proliferation and metabolism of lung cancer cells, and the mechanism by which sex hormones and their receptors influence lung cancer is worthy of further research.

[The influence of miR-21 on HK-2 EMT cells induced by TGF-beta 1].

OBJECTIVE: To investigate the effect of the miR-21 and its target mRNA in renal tubular epithelial mesenchymal transformation (EMT) model induced by transformation growth factor-ß1(TGF-ß1) in human renal tubular epithelial (HK-2) cells. METHODS: HK-2 cells were divided into 6 groups:normal control group, TGF-ß1 group, miR-21 mimic negative group, miR-21 mimic group, miR-21 inhibitor negative group and miR-21 inhibitor group. EMT model was established in HK-2 cells induced by 4 ng/ml TGF-ß1. The level of miR-21, the mRNA and protein expression of EMT related factors were detected. MiR-21 mimic plasmid and miR-21 inhibitor plasmid were transfected into HK-2 cells that treated with TGF-ß1 respectively using liposome transfection technique. Observe the impact of overexpression or inhibition expression of miR-21 on the mRNA and protein expression of EMT related factors and PTEN. RESULTS: ①Compared with the normal group, the level of miR-21 was significantly increased in model group (P<0.05), the mRNA and protein expression levels of epithelial cells marker E-cadherin was significantly decreased (P<0.01), while the mRNA and protein levels of mesenchymal cells marker α-SMA was significantly increased (P<0.05,P<0.01). ②Compared with the miR-21 mimic negative group, the level of miR-21 in miR-21 mimic group increased significantly (P<0.01), the mRNA and protein expression levels of PTEN and E-cadherin decreased significantly (P<0.05,P<0.01), the mRNA and protein levels of α-SMA increased significantly (P<0.05,P<0.01). Compared with the miR-21 inhibitor negative control group, the level of miR-21 in miR-21 inhibitor group decreased significantly (P<0.01), the mRNA and protein expression levels of PTEN and E-cadherin increased significantly (P<0.05,P<0.01), the mRNA and protein levels of α-SMA decreased significantly (P<0.05,P<0.01). CONCLUSIONS: MiR-21 may play an important role in EMT induced by TGF-ß1 in HK-2 cells and regulate the expression of EMT related factors its target gene PTEN.

[Experimental research on the prevention of rabbit postoperative abdominal cavity adhesion with PLGA membrane].

The aim of this paper is to explore the prevention of rabbit postoperative abdominal cavity adhesion with poly (lactic-co-glycotic acid) (PLGA) membrane and the mechanism of this prevention function. Sixty-six Japanese white rabbits were randomly divided into normal control group, model control group and PLGA membrane group. The rabbits were treated with multifactor methods to establish the postoperative abdominal cavity adhesion models except for those in the normal control group. PLGA membrane was used to cover the wounds of rabbits in the PLGA membrane group and nothing covered the wounds of rabbits in the model control group. The hematologic parameters, liver and kidney functions and fibrinogen contents were detected at different time. The rabbit were sacrificed 1, 2, 4, 6, 12 weeks after the operations, respectively. The adhesions were graded blindly, and Masson staining and immunohistochemistry methods were used to observe the proliferation of collagen fiber and the expression of transforming growth factor ß1 (TGF-ß1) on the cecal tissues, respectively. The grade of abdominal cavity adhesion showed that the PLGA membrane-treated group was significant lower than that in the model control group, and it has no influence on liver and kidney function and hematologic parameters. But the fibrinogen content and the number of white blood cell in the PLGA membrane group were significant lower than those of model control group 1 week and 2 weeks after operation, respectively. The density of collagen fiber and optical density of TGF-ß1 in the PLGA membrane group were significant lower than those of model control group. The results demonstrated that PLGA membrane could be effective in preventing the abdominal adhesions in rabbits, and it was mostly involved in the reducing of fibrinogen exudation, and inhibited the proliferation of collagen fiber and over-expression of TGF-ß1.

Transcriptomic analysis of hepatic responses to testosterone deficiency in miniature pigs fed a high-cholesterol diet.

BACKGROUND: Recent studies have indicated that low serum testosterone levels are associated with increased risk of developing hepatic steatosis; however, the mechanisms mediating this phenomenon have not been fully elucidated. To gain insight into the role of testosterone in modulating hepatic steatosis, we investigated the effects of testosterone on the development of hepatic steatosis in pigs fed a high-fat and high-cholesterol (HFC) diet and profiled hepatic gene expression by RNA-Seq in HFC-fed intact male pigs (IM), castrated male pigs (CM), and castrated male pigs with testosterone replacement (CMT). RESULTS: Serum testosterone levels were significantly decreased in CM pigs, and testosterone replacement attenuated castration-induced testosterone deficiency. CM pigs showed increased liver injury accompanied by increased hepatocellular steatosis, inflammation, and elevated serum alanine aminotransferase levels compared with IM pigs. Moreover, serum levels of total cholesterol, low-density lipoprotein cholesterol, and triglycerides were markedly increased in CM pigs. Testosterone replacement decreased serum and hepatic lipid levels and improved liver injury in CM pigs. Compared to IM and CMT pigs, CM pigs had lower serum levels of superoxide dismutase but higher levels of malondialdehyde. Gene expression analysis revealed that upregulated genes in the livers of CM pigs were mainly enriched for genes mediating immune and inflammatory responses, oxidative stress, and apoptosis. Surprisingly, the downregulated genes mainly included those that regulate metabolism-related processes, including fatty acid oxidation, steroid biosynthesis, cholesterol and bile acid metabolism, and glucose metabolism. KEGG analysis showed that metabolic pathways, fatty acid degradation, pyruvate metabolism, the tricarboxylic acid cycle, and the nuclear factor-kappaB signaling pathway were the major pathways altered in CM pigs. CONCLUSIONS: This study demonstrated that testosterone deficiency aggravated hypercholesterolemia and hepatic steatosis in pigs fed an HFC diet and that these effects could be reversed by testosterone replacement therapy. Impaired metabolic processes, enhanced immune and inflammatory responses, oxidative stress, and apoptosis may contribute to the increased hepatic steatosis induced by testosterone deficiency and an HFC diet. These results deepened our understanding of the molecular mechanisms of testosterone deficiency-induced hepatic steatosis and provided a foundation for future investigations.

Effect of testosterone deficiency on cholesterol metabolism in pigs fed a high-fat and high-cholesterol diet.

BACKGROUND: Testosterone deficiency is associated with increased serum cholesterol levels. However, how testosterone deficiency precisely affects cholesterol metabolism remains unclear. Therefore, in the current study, we examined the effect of testosterone deficiency on cholesterol metabolism and liver gene expression in pigs fed a high-fat and high-cholesterol (HFC) diet. METHODS: Sexually mature male miniature pigs (6-7 months old) were randomly divided into 3 groups as follows: intact male pigs fed an HFC diet (IM+HFC), castrated male pigs fed an HFC diet (CM+HFC), and castrated pigs with testosterone replacement fed an HFC diet (CM+HFC+T). Serum testosterone levels and lipid profiles were measured, and gene expression levels associated with hepatic cholesterol metabolism were determined. Furthermore, total hepatic cholesterol contents and the activities of enzymes mediating hepatic cholesterol metabolism were measured. RESULTS: Serum testosterone levels were significantly decreased in CM+HFC pigs, and testosterone replacement attenuated castration-induced testosterone deficiency. Castration significantly increased the serum levels of total cholesterol, low-density lipoprotein cholesterol and triglycerides, as well as hepatic lipid contents in pigs fed an HFC diet. Compared with IM+HFC and CM+HFC+T pigs, low-density lipoprotein receptor (LDLR) mRNA expression and protein levels were significantly decreased in the livers of CM+HFC pigs. In contrast, we found that compared with IM+HFC pigs, hepatic proprotein convertase subtilisin/kexin type 9 (PCSK9) mRNA and serum PCSK9 protein levels were significantly increased in CM+HFC pigs. Moreover, testosterone treatment reversed the increase in PCSK9 expression in CM+HFC pigs. However, neither castration nor testosterone replacement affected the expression of the other hepatic genes that were tested. CONCLUSIONS: This study demonstrated that castration-induced testosterone deficiency caused severe hypercholesterolemia in pigs fed an HFC diet; furthermore, these effects could be reversed by testosterone replacement therapy. Altered hepatic PCSK9 and LDLR expression, resulting in reduced LDL-cholesterol clearance, may contribute to the increased serum cholesterol levels induced by testosterone deficiency and an HFC diet. These results deepen our understanding of the underlying molecular mechanisms that mediate the effects of testosterone deficiency on cholesterol metabolism.

[Effects of PLGA absorbable membrane on preventing postoperative abdominal adhesion in rabbits].

OBJECTIVE: To investigate the effects of PLGA absorbable membrane in prevention of postoperative abdominal adhesion in rabbits. METHODS: 66 Japanese white rabbits were randomly divided into three groups: the normal control group n = 6, model control group n = 30 and PLGA group n = 30. Rabbits were received multifactor methods to establish postoperative abdominal adhesion models except for normal control group. The cecum wound was covered PLGA membrane in the PLGA group. At postoperative 1, 2, 4, 6 and 12 weeks, the abdominal cavities were reopened and the adhesive severity was graded blindly, and the hydroxyproline level in cecum tissue was measured and the cecum histopathology was observed. RESULTS: (1) the degree of adhesion and hydroxyproline level in model control group were significantly higher than those of normal control group (P < 0.05, P < 0.01), while the degree of adhesion and hydroxyproline level in PLGA group were significantly lower than those of model control group (P < 0.05). (2) HE staining showed that cecum serosa had obviously inflammatory cell infiltration and fibroblast proliferation, while PLGA could inhibit fibroblast proliferation and reduce the inflammatory cell infiltration and collagen. CONCLUSION: PLGA absorbable membrane can inhibit fibroblast proliferation and collagen to prevent the experimental postoperative peritoneal adhesions.

[Effect of Nrf2 and related factors on the progression of nonalcoholic steatohepatitis].

OBJECTIVE: To explore the role of NF-E2-related factor 2(Nrf2) and its related factors in the progression of nonalcoholi steatohepatitis (NASH) by investigating the alterations of lipid metabolism and liver histopathology as well as the changes of mRNA and protein expression levels of Nrf2 and its related factors in rats during NASH progression. METHODS: Male SD rats were randomly divided into normal group and model group, which were administrated with high fat diet to establish nonalcoholic steatohepatitis model. The rats from both groups were randomly killed at the end of 4, 12 weeks respectively. The levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total cholesterol (TC), triglyceride (TG), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C) were detected in the serum and liver tissue; Changes in fat deposition in liver tissue were determined by oil red O staining. HE staining were used to observe the pathological changes of liver tissue and to calculate nonalcoholic fatty liver disease (NAFLD) activity score (hepatic steatosis, inflammation and ballooning degeneration of liver cells). The expression of Nrf2 in liver was detected by immunohistochemical staining. The mRNA and protein levels of Nrf2 and related factors in liver were determined by Realtime PCR and Western blot, respectively. RESULTS: After 4 weeks of high fat diet, the levels of ALT, AST, TC in rat serum and TC, TG, LDL-C in liver were significantly increased compared with that of the normal group (P < 0.01, P < 0.05). After 4 weeks of high fat diet, the levels of ALT, AST, TC, TG in serum and TC, TG, LDL- C in liver increased further (P < 0.01, P < 0.05). Until the 12th week, the content of HDL-C in liver was significantly lower than that of the normal group (P < 0.05). At the end of the 4th or the 12th week, lipid droplets in the model rat liver cells were heavily dyed red and hepatic steatosis increased severely, with ballooning degeneration of liver cells. With the extension of high fat diet feeding time, fat deposition in the liver tissue, hepatic steatosis, NAFLD score, Nrl2 expression were significantly increased (P < 0.01). Expression levels of mRNA and protein of Nrf2, heme oxyenase 1(HO1), NADPH quinone oxidoreductase 1(NQO1), γ-glutamylcysteine synthethase (γ-GCS), glutathione S-transferase (GST) in the model rats increased or decreased at the end of the 4th or the 12th week differentially, (P < 0.01, P < 0.05) with the more significant changes at the end of the 4th week than the 12th week. CONCLUSION: Nrf2 and its related factors may be involved in the occurrence and development of nonalcoholic fatty liver disease, which may play an important role in the process of NASH formation.

[Effects of soybean trypsinase inhibitor and defense signaling compounds on detoxification enzymes in Spodoptera litura (F.) larvae].

In a long history of interactions between insects and plants, plants have developed various anti-insect compounds and defense signaling transduction pathways to defend against herbivorous insects, while insects have responded with sophisticated detoxification enzyme systems to protect against the toxicity of anti-insect compounds. In this study, the 2nd or 3rd instar of Spodoptera litura larvae were successively fed with the diets containing 0.5% soybean trypsinase inhibitor (SBTI) for six generations to evaluate the effects of SBTI and defense signaling compounds on the activities of detoxification enzymes carboxylesterase (CarE) and glutathione-S-transferase (GST) in the midgut and fatbody of the larvae. After fed with the diets, the CarE and GST activities in the 5th instar larvae increased significantly. The CarE activity in the midgut and fatbody of the second generation larvae was the highest, being 2.06 and 2.40 times, and 1.96 and 2.70 times of that of the control, and the GST activity in the midgut and fatbody of the fourth and second generations was the highest, being 7.03 and 11.58 times, and 5.71 and 3.60 times of that of the control, respectively. These induced enzyme activities decreased gradually when the larvae continuously grew with the SBTI-containing diets. In addition, when the S. litura larvae were pre-exposed to methyl jasmonate (MeJA) or methyl salicylate (MeSA) for 48 h or fed with the diets containing 0.5% SBTI, the activities of CarE and GST in the midgut and fatbody increased significantly, and, when the 2nd instar larvae were pre-exposed to MeJA and MeSA for 48 h, the effects of SBTI on the GST activity in larval midgut and fatbody were reduced.