Characterized profiles of gut microbiota in morphine abstinence-induced depressive-like behavior.

Morphine is the most widely used analgesic for pain management worldwide. Abstinence of morphine could lead to neuropsychiatric symptoms, including depression. Gut microbiota is believed to contribute to the development of depression. However, the characteristics and potential role of gut microbiota in morphine abstinence-induced depression remain unclear. In the present study, we first established morphine abstinence-induced depressive behavior in mice. After dividing the mice into depressive and non-depressive groups, the gut microbiota of the mice was detected by 16S rRNA gene sequencing. The difference in the diversities and abundance of the gut microbiota were analyzed between groups. Then, the representative microbial markers that could distinguish each group were identified. In addition, gene function prediction of the operational taxonomic units (OTUs) with differential abundance between the depressive and non-depressive groups after morphine abstinence was conducted. Our results suggested that four weeks of abstinence from morphine did not change the richness of the gut microbiota. However, morphine abstinence influenced the gut microbial composition. Several specific genera of gut microbiota were identified as markers for each group. Interestingly, gene function prediction found that the fatty acid metabolism pathway was enriched in the OUTs in the depressive group compared with the non-depressive group after morphine abstinence. Our data suggested that gut microbiota dysbiosis was associated with morphine abstinence-induced depressive behavior, possibly by implicating the fatty acid metabolism pathway.

Expression Quantitative Trait Locus rs6356 Is Associated with Susceptibility to Heroin Addiction by Potentially Influencing TH Gene Expression in the Hippocampus and Nucleus Accumbens.

Opioid addiction is a complicated and highly heritable brain disease. Dysfunction in dopaminergic signaling is involved in the pathogenesis of addictive disorders. Encoding a dopamine synthetase, the tyrosine hydroxylase (TH) gene has long been an interesting candidate in genetic association studies for opioid addiction. However, the mechanisms underlying associations of risk gene variants and opioid addiction remain unknown. In the present study, we first analyzed the association between TH gene variants and susceptibility and traits of heroin addiction in 801 patients with heroin addiction and 930 healthy controls. Methylation levels in the promoter region of the TH gene were detected and compared between the heroin addiction and healthy control groups. To reveal the potential mechanism of the association of TH gene variants and heroin addiction, correlations between the risk TH single nucleotide polymorphism (SNPs) for heroin addiction and the methylation and expression levels of the TH gene were examined. Our results demonstrated that SNP rs6356 was associated with susceptibility to heroin addiction. CpG TH_15 was hypermethylated in the heroin addiction group compared with the healthy control group. Notably, SNP rs6356 was correlated in an allele-specific manner with expression of the TH gene in the hippocampus and nucleus accumbens but not with methylation levels of CpG TH_15. Our findings suggest that the eQTL rs6356 was associated with susceptibility to heroin addiction by potentially affecting the expression of the TH gene in brain regions in the mesocorticolimbic dopamine system, including the hippocampus and nucleus accumbens.

Fibroblast­derived exosomal microRNA­369 potentiates migration and invasion of lung squamous cell carcinoma cells via NF1­mediated MAPK signaling pathway.

Cancer­associated fibroblasts (CAFs) exhibit tumor­stimulating properties and are associated with poor survival in several types of cancer, making them potential therapeutic targets. The present study aimed to determine whether CAFs were associated with cell migration and invasion in lung squamous cell carcinoma (LUSC), as well as their association with microRNA­369 (miR­369) in these processes. Firstly, the changes of the malignant biological behavior were observed by treating the LUSC cells with the CAFs­derived extracellular vesicles (CAFs­EVs). Subsequently, the differentially expressed miRNAs in the cells treated with CAFs­EVs were analyzed by microarray analysis. Following inhibition of miR­369 expression in CAFs­EVs, LUSC cells were co­cultured, and the malignant biological behavior of the cells was re­examined. Then, through bioinformatics analysis and verification, the mRNA targets of miR­369 and the corresponding downstream signaling pathway were screened out. Finally, the effects of CAFs­EVs on the growth and metastasis of LUSC were demonstrated by in vivo tumor formation and metastasis experiments. It was identified that miR­369 was expressed at a relatively high level in the CAFs­EVs. Neurofibromin­1 (NF1) was hypothesized as a direct target of miR­369 in LUSC. Also, the overexpression of miR­369 activated the mitogen­activated protein kinase signaling pathway by interacting with NF1, consequently potentiating LUSC cell growth. The present study provided novel insights into the action of miR­369 in CAFs­EVs in controlling LUSC cell migration, invasion and tumorigenesis, and identified miR­369 in CAFs­EVs as an important prognostic marker and therapeutic target.

MicroRNA­663b targets GAB2 to restrict cell proliferation and invasion in hepatocellular carcinoma.

Previous studies have demonstrated that numerous tumor­specific microRNAs (miRNAs) are upregulated or downregulated in hepatocellular carcinoma (HCC), and that their dysregulation is implicated in HCC occurrence and development. Therefore, investigation of crucial miRNAs involved in HCC oncogenesis and progression may provide novel insights into the therapy of patients with this malignant tumor. In the present study, reverse transcription­quantitative polymerase chain reaction (RT­qPCR) assays were performed to detect tissue and cellular expression levels of miRNA­663b (miR­663b) in HCC. The effects of miR­663b overexpression on the proliferation and invasion of HCC cells were examined using Cell Counting Kit­8 and Transwell invasion assays, respectively. The direct target of miR­663b in HCC cells was determined by bioinformatics analysis, luciferase reporter assay, RT­qPCR and western blot analysis. It was observed that miR­663b was expressed at low levels in HCC tissues and cell lines. miR­663b upregulation suppressed the proliferative and invasive abilities of HCC cells. Additionally, Grb2­associated binding 2 (GAB2) was regarded as a direct target gene of miR­663b in HCC cells. Furthermore, GAB2 was overexpressed in HCC tissues, and overexpression of GAB2 was inversely correlated with levels of miR­663b. GAB2 overexpression was able to rescue the suppressive effects of miR­663b on HCC cells. These results demonstrated that this newly­identified miR­663b/GAB2 axis may be implicated in HCC occurrence and development.

Effect of Stay-Green Wheat, a Novel Variety of Wheat in China, on Glucose and Lipid Metabolism in High-Fat Diet Induced Type 2 Diabetic Rats.

The use of natural hypoglycemic compounds is important in preventing and managing Type 2 diabetes mellitus (T2DM). Forty male Sprague-Dawley rats weighing 150-180 g were divided into four groups to investigate the effects of the compounds in stay-green wheat (SGW), a novel variety of wheat in China, on T2DM rats. The control group (NDC) was fed with a standard diet, while T2DM was induced in the rats belonging to the other three groups by a high-fat diet followed by a streptozotocin (STZ) injection. The T2DM rats were further divided into a T2DM control group (DC), which was fed with the normal diet containing 50% common wheat flour, a high dose SGW group (HGW) fed with a diet containing 50% SGW flour, and a low dose SGW group (LGW) fed with a diet containing 25% SGW flour and 25% common wheat flour. Our results showed that SGW contained cereal antioxidants, particularly high in flavonoids and anthocyanins (46.14 ± 1.80 mg GAE/100 g DW and 1.73 ± 0.14 mg CGE/100 g DW, respectively). Furthermore, SGW exhibited a strong antioxidant activity in vitro (30.33 ± 2.66 µg TE/g DW, p < 0.01). Administration of the SGW at a high and low dose showed significant down-regulatory effects on fasting blood glucose (decreasing by 11.3% and 7.0%, respectively), insulin levels (decreasing by 12.3% and 9.7%, respectively), and lipid status (decreasing by 9.1% and 7.5%, respectively) in T2DM rats (p < 0.01). In addition, the T2DM groups treated with SGW at a high and low dose showed a significant increase in the blood superoxide dismutase (1.17 fold and 1.15 fold, respectively) and glutathione peroxidase activities (1.37 fold and 1.30 fold, respectively) compared with the DC group (p < 0.01). The normalized impaired antioxidant status of the pancreatic islet and of the liver compared with the DC group was also significantly increased. Our results indicated that SGW components exerting a glycemic control and a serum lipid regulation effect may be due to their free radical scavenging capacities to reduce the risk of T2DM in experimental diabetic rats.