Profiling of GABAA and GABAB receptor expression in the myometrium of the human uterus

Morphology and Chemical Messenger Regulation of Echinoderm Muscles

The muscular systems of echinoderms play important roles in various physiological and behavioral processes, including feeding, reproduction, movement, respiration, and excretion. Like vertebrates, echinoderm muscle systems can be subdivided into two major divisions, somatic and visceral musculature. The former usually has a myoepithelial organization, while the latter contains muscle bundles formed by the aggregation of myocytes. Neurons and their processes are also detected between these myoepithelial cells and myocytes, which are capable of releasing a variety of neurotransmitters and neuropeptides to regulate muscle activity. Although many studies have reported the pharmacological effects of these chemical messengers on various muscles of echinoderms, there has been limited research on their receptors and their signaling pathways. The muscle physiology of echinoderms is similar to that of chordates, both of which have the deuterostome mode of development. Studies of muscle regulation in echinoderms can provide new insights into the evolution of myoregulatory systems in deuterostomes.

A Nested Case-Control Study of Allopregnanolone and Preterm Birth in the Healthy Start Cohort

Context

Chronic stress is a risk factor for preterm birth; however, objective measures of stress in pregnancy are limited. Maternal stress biomarkers may fill this gap. Steroid hormones and neurosteroids such as allopregnanolone (ALLO) play important roles in stress physiology and pregnancy maintenance and therefore may be promising for preterm birth prediction.

Objective

We evaluated maternal serum ALLO, progesterone, cortisol, cortisone, pregnanolone, and epipregnanolone twice in gestation to evaluate associations with preterm birth.

Methods

We performed a nested case-control study using biobanked fasting serum samples from the Healthy Start prebirth cohort. We included healthy women with a singleton pregnancy and matched preterm cases with term controls (1:1; N = 27 per group). We used a new HPLC-tandem mass spectrometry assay to quantify ALLO and five related steroids. We used ANOVA, Fisher exact, χ², t test, and linear and logistic regression as statistical tests.

Results

Maternal serum ALLO did not associate with preterm birth nor differ between groups. Mean cortisol levels were significantly higher in the preterm group early in pregnancy (13w0d-18w0d; P < 0.05) and higher early pregnancy cortisol associated with increased odds of preterm birth (at 13w0d; odds ratio, 1.007; 95% CI, 1.0002-1.014). Progesterone, cortisone, pregnanolone, and epipregnanolone did not associate with preterm birth.

Conclusion

The findings from our pilot study suggest potential utility of cortisol as a maternal serum biomarker for preterm birth risk assessment in early pregnancy. Further evaluation using larger cohorts and additional gestational timepoints for ALLO and the other analytes may be informative.

Potential mechanism of the Shunaoxin pill for preventing cognitive impairment in type 2 diabetes mellitus

Objective

This study aims to analyze the efficacy and mechanism of action of the Shunaoxin pill in preventing cognitive impairment in diabetic patients using network pharmacology.

Methods

The main active compounds of the Shunaoxin pills and their action targets were identified via the TCMSP and Batman-TCM databases. The GEO database was used to identify the genes in type 2 diabetic individuals associated with cognitive impairment. Subsequently, a common target protein-protein interaction (PPI) network was constructed using the STRING database, and targets associated with diabetes and cognitive impairment were screened by performing a topological analysis of the PPI network. The AutoDock Vina software was used for molecular docking to evaluate the reliability of the bioinformatic analysis predictions and validate the interactions between the active ingredients of the Shunaoxin pill and proteins associated with diabetes and cognitive impairment.

Results

Based on the TCMSP and Batman-Tcm platform, 48 active ingredients of the Shunaoxin pill were identified, corresponding to 222 potential action targets. Further analysis revealed that 18 active components of the Shunaoxin pill might contribute to cognitive impairment in type 2 diabetic patients. Molecular docking simulations demonstrated that the active ingredients of the Shunaoxin pill (hexadecanoic acid, stigmasterol, beta-sitosterol, and angelicin) targeted four core proteins: OPRK1, GABRA5, GABRP, and SCN3B.

Conclusion

Active ingredients of the Shunaoxin pill may alleviate cognitive impairment in diabetic patients by targeting the proteins OPRK1, GABRA5, GABRP, and SCN3B.

A Brief History and the Significance of the GABAB Receptor

γ-Aminobutyric acid (GABA) is the main inhibitory neurotransmitter in the brain. GABA type B (GABA_B) receptors (GABA_BRs) are the only metabotropic G protein-coupled receptors for GABA and can be found distributed not only in the central nervous system, but also in the periphery. This chapter introduces important, fundamental knowledge related to GABA_BR function and the various potential therapeutic applications of the development of novel GABA_BR-active compounds, as documented through extensive studies presented in subsequent chapters of this Current Topic in Behavioral Neurosciences volume on the role of the neurobiology of GABA_BR function. The compounds that have received increased attention in the last few years compared to GABA_BR agonists and antagonists - the positive allosteric modulators - exhibit better pharmacological profiles and fewer side effects. As we continue to unveil the mystery of GABA_BRs at the molecular and cellular levels, we further understand the significance of these receptors. Future directions should aim for developing highly selective GABA_BR compounds for treating neuropsychiatric disorders and their symptomatology.

Effects of activating GABAB1 receptor on proliferation, migration, invasion and epithelial-mesenchymal transition of ovarian cancer cells

OBJECTIVE

This study aimed to explore the effects of activating GABAB1 receptor by baclofen on proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) of ovarian cancer cells.

RESULTS

One hundred μmol/L, 200 μmol/L and 300 μmol/L were selected as low, medium and high baclofen concentrations respectively. Cells were divided into four groups: Control, 100 μmol/L, 200 μmol/L and 300 μmol/L. Compared with the control group, the viability, colony formation, migration and invasion of SKOV3 cells were inhibited, and the apoptosis of SKOV3 cells were enhanced significantly at 200 μmol/L and 300 μmol/L baclofen. Moreover, they changed significantly with the increase of baclofen concentration. Compared with the control group, the expression of E-cadherin and GABAB1 increased and the N-cadherin expression decreased significantly in 200 μmol/L and 300 μmol/L groups. Higher concentration of baclofen induced higher expression of E-cadherin and lower expression of N-cadherin.

CONCLUSION

Baclofen inhibited the proliferation, cloning, migration, invasion and EMT of ovarian cancer cells by activating GABAB1 receptor. These results might contribute a lot to clarify the role and possible mechanism of GABAB1 receptor in ovarian cancer.

Pinocembrin inhibits the proliferation and migration and promotes the apoptosis of ovarian cancer cells through down-regulating the mRNA levels of N-cadherin and GABAB receptor

There is no previous study on the effect of pinocembrin on ovarian cancer to the best of our knowledge. Moreover, the effects of pinocembrin on the expression of GABAB1 and GABAB2 genes are not studied before. Therefore, this study aimed to investigate effects of pinocembrin on the growth of ovarian cancer cells and the expression of cadherin and GABAB receptor to explore whether pinocembrin was helpful in the treatment of epithelial ovarian cancer. SKOV3 cells were divided into six groups: Control (blank control), DDP (cisplatin as positive control; cells were incubated with 15 μg/ml DDP), 25 μM (cells were incubated with 25 μM pinocembrin), 50 μM (cells were incubated with 50 μM pinocembrin), 100 μM (cells were incubated with 100 μM pinocembrin), and 200 μM (cells were incubated with 200 μM pinocembrin). CCK8 assay, cell scratch assay and Annexin V-FITC/PI staining found that when pinocembrin concentration reached 100 μM and the treatment time reached 48 h, pinocembrin could inhibit the cell proliferation and migration and promote the cell apoptosis, and this effect was enhanced with the increase of pinocembrin concentration. Western blotting found that the protein expression of E-cadherin, N-cadherin, GABAB1 and GABAB2 was not significantly affected by pinocembrin. RT-PCR found that pinocembrin also had no significant influence on the E-cadherin mRNA level, but it could reduce the mRNA levels of N-cadherin, GABAB1 and GABAB2. In conclusion, pinocembrin inhibited the proliferation and migration and promoted the apoptosis of ovarian cancer cells through down-regulating the mRNA levels of N-cadherin and GABAB receptor.