Neuronal and Molecular Mechanisms Underlying Chronic Pain and Depression Comorbidity in the Paraventricular Thalamus.

Patients with chronic pain often develop comorbid depressive symptoms, which makes the pain symptoms more complicated and refractory. However, the underlying mechanisms are poorly known. Here, in a repeated complete Freund's adjuvant (CFA) male mouse model, we reported a specific regulatory role of the paraventricular thalamic nucleus (PVT) glutamatergic neurons, particularly the anterior PVT (PVA) neurons, in mediating chronic pain and depression comorbidity (CDC). Our c-Fos protein staining observed increased PVA neuronal activity in CFA-CDC mice. In wild-type mice, chemogenetic activation of PVA glutamatergic neurons was sufficient to decrease the 50% paw withdrawal thresholds (50% PWTs), while depressive-like behaviors evaluated with immobile time in tail suspension test (TST) and forced swim test (FST) could only be achieved by repeated chemogenetic activation. Chemogenetic inhibition of PVA glutamatergic neurons reversed the decreased 50% PWTs in CFA mice without depressive-like symptoms and the increased TST and FST immobility in CFA-CDC mice. Surprisingly, in CFA-CDC mice, chemogenetically inhibiting PVA glutamatergic neurons failed to reverse the decrease of 50% PWTs, which could be restored by rapid-onset antidepressant S-ketamine. Further behavioral tests in chronic restraint stress mice and CFA pain mice indicated that PVA glutamatergic neuron inhibition and S-ketamine independently alleviate sensory and affective pain. Molecular profiling and pharmacological studies revealed the 5-hydroxytryptamine receptor 1D (Htr1d) in CFA pain-related PVT engram neurons as a potential target for treating CDC. These findings identified novel CDC neuronal and molecular mechanisms in the PVT and provided insight into the complicated pain neuropathology under a comorbid state with depression and related drug development.

Adulthood bisphenol A exposure induces anxiety in male mice via downregulation of alpha-1D adrenergic receptor in paraventricular thalamus.

Bisphenol A (BPA), a ubiquitous endocrine disrupting chemical, is widely used in household plastic products. Large amounts of evidence indicate prenatal and postnatal BPA exposure causes neurodevelopmental disorders such as anxiety and autism. However, the neuronal mechanisms underlying the neurotoxic effects of adulthood BPA exposure remain poorly understood. Here, we provided evidences that adult mice treated with BPA (0.45 mg/kg/day) during 3 weeks exhibited sex-specific anxiety like behaviors. We demonstrated that the BPA-induced anxiety in male mice, but not in female mice, was closely associated with hyperactivity of glutamatergic neurons in the paraventricular thalamus (PVT). Acute chemogenetic activation of PVT glutamatergic neurons caused similar effects on anxiety as observed in male mice exposed to BPA. In contrast, acute chemogenetic inhibition of PVT glutamatergic neurons reduced BPA-induced anxiety in male mice. Concomitantly, the BPA-induced anxiety was related with a down-regulation of alpha-1D adrenergic receptor in the PVT. Taken together, the present study indicated a previously unknown target region in the brain for neurotoxic effects of BPA on anxiety and implicated a possible molecular mechanism of action.

Establishment of humanized mice and its application progress in cancer immunotherapy.

The current high prevalence of malignant tumors has attracted considerable attention, and treating advanced malignancies is becoming increasingly difficult. Although immunotherapy is a hopeful alternative, it is effective in only a few people. Thus, development of preclinical animal models is needed. Humanized xenotransplantation mouse models can help with selecting treatment protocols, evaluating curative effects and assessing prognosis. This review discusses the establishment of humanized mouse models and their application prospects in cancer immunotherapy to identify tailored therapies for individual patients.

Immunotherapy is a promising treatment option for patients with advanced malignant tumors; however, it is not effective in all patients. Therefore, it is particularly important to identify effective preclinical models and develop individualized treatment plans for each patient. Humanized animal models can simulate the human immune microenvironment, enabling comprehensive evaluation of the efficacy, safety and feasibility of various immunotherapy strategies. Such models provide a theoretical basis for the individualized treatment of patients with advanced malignant tumors as well as serving as a promising medium for the research and development of preclinical drugs.

Boric acid was orally toxic to different instars of Blattella germanica (L.) (Blattodea: Blattellidae) and caused dysbiosis of the, gut microbiota.

Boric acid, a well-established chemical insecticide, has a good control effect on various types of cockroaches. In this study, we investigated the oral virulence effect of boric acid on German cockroach (Blattella germanica) of various instars and characterized its effect on the gut microbiota by high-throughput sequencing technology. The results of an oral toxicity test showed that the toxicity of boric acid was positively correlated with its concentration and negatively correlated with the instar of cockroach nymphs. The 1-3 instar nymphs showed the strongest sensitivity to boric acid, which exhibited a median lethal time of only 3.16 d, while the 6-7 instar nymphs showed the weakest sensitivity, and exhibited a median lethal time of 10.15 d. There was no significant difference between male and female insects regarding their sensitivity to boric acid. Oral treatment of boric acid resulted in severe dysbiosis in cockroaches, the relative abundances of Bacteroides, which can degrade a variety of complex macromolecules, and Enterococcus, which can inhibit pathogenic microorganisms, were significantly reduced, while the relative abundance of the opportunistic pathogenic bacterium Weissella was significantly increased. It was speculated that dysbiosis of gut microbiota might accelerate the toxicity of boric acid on German cockroaches.

New Insights into Cockroach Control: Using Functional Diversity of Blattella germanica Symbionts.

Insects have close symbiotic relationships with several microbes, which extends the limited metabolic networks of most insects. Using symbiotic microorganisms for the biological control of pests and insect-borne diseases has become a promising direction. Blattella germanica (L.) (Blattaria: Blattidae) is a public health pest worldwide, which is difficult to control because of its strong reproductive ability, adaptability, and resistance to insecticides. In this paper, the diverse biological functions (nutrition, reproductive regulation, insecticide resistance, defense, and behavior) of symbionts were reviewed, and new biological control strategies on the basis of insect-symbiont interaction were proposed. We highlight new directions in B. germanica control, such as suppressing cockroach population using Wolbachia or paratransgenes, and combining fungal insecticides with synergistic agents to enhance insecticidal efficacy.

Effects of Antibiotics on the Dynamic Balance of Bacteria and Fungi in the Gut of the German Cockroach.

The German cockroach, Blattella germanica (L.) (Blattaria: Blattidae) harbored diverse microorganisms in the digestive tract, including bacteria, fungi, viruses, archaea, and protozoa. This diverse community maintains a relatively stable balance. Some bacteria have been confirmed to play crucial roles in the insect's physiology, biochemistry, and behavior. Antibiotics can effectively eliminate bacteria and disrupt the balance of gut microbiota, but the time-course of this process, the structure of the new microbial community, and the dynamics of re-assemblage of a bacterial community after antibiotic treatment have not been investigated. In the present study, antibiotic (levofloxacin and gentamicin) ingestion reduced bacterial diversity and abundance in the cockroach gut. Within 14 d of discontinuing antibiotic treatment, the number of culturable gut bacteria returned to its original level. However, the composition of the new bacterial community with greater abundance of antibiotic-resistant Enterococcus and Dysgonomonas was significantly different from the original community. Network analysis showed that antibiotic treatment made the interaction between bacteria and fungi closer and stronger in the cockroach gut during the recovery of gut microorganisms. The study on the composition change, recovery rules, and interaction dynamics between gut bacteria and fungi after antibiotic treatment are helpful to explore gut microbes' colonization and interaction with insects, which contributes to the selection of stable core gut bacteria as biological carriers of paratransgenesis for controlling Blattella germanica.

NF-κB-driven miR-34a impairs Treg/Th17 balance via targeting Foxp3.

The subset of regulatory T (Treg) cells, with its specific transcription Foxp3, is a unique cell type for the maintenance of immune homeostasis by controlling effector T (Teff) cell responses. Although it is common that a defect in Treg cells with Treg/Teff disorder causes autoimmune diseases; however, the precise mechanisms are not thoroughly revealed. Here, we report that miR-34a could attenuate human and murine Foxp3 gene expression via targeting their 3' untranslated regions (3' UTR). The human miR-34a, increased in peripheral blood mononuclear cells (PBMCs) and CD4+ T cells from rheumatoid arthritis (RA) or systemic lupus erythematosus (SLE) patients, displayed a positive correlation with some serum markers of inflammation including rheumatoid factor (RF), anti-streptolysin antibody (ASO), erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) as well as Th17 signature gene RORγt, but inversely correlated with the mRNA expression levels of FOXP3. In addition, murine miR-34a levels were downregulated in TGF-ß-induced Treg cells but upregulated in Th17 cells induced in vitro compared to activated CD4+ T cells. It has also been demonstrated that elevated miR-34a disrupting Treg/Th17 balance in vivo contributed to the progress of pathogenesis of collagen induced arthritis (CIA) mice. Furthermore, IL-6 and TNF-α were responsible for the upregulation of miR-34a and downregulation of Foxp3, which was reverted by the addition of NF-κB/p65 inhibitor BAY11-7082, thus indicating that NF-κB/p65 inhibited Foxp3 expression in an miR-34a-dependent manner. Finally, IL-6 or TNF-α-activated p65 could bind to the miR-34a promotor and enhance its activity, resulting in upregulation of its transcription. Taken together, we show that NF-κB activated by inflammatory cytokines, such as IL-6 and TNF-α, ameliorates Foxp3 levels via regulating miR-34a expression, which provides a new mechanistic and therapeutic insight into the ongoing of autoimmune diseases.

miR-34a and miR-125b are upregulated in peripheral blood mononuclear cells from patients with type 2 diabetes mellitus.

Type 2 diabetes mellitus (T2DM) is a leading cause of blindness, non-traumatic amputation and end-stage renal disease, as well as a major cardiovascular risk factor. To determine whether miR-125b and miR-34a serve an important role in the development of T2DM, the current study investigated the expression profile of two microRNAs (miR-34a and miR-125b) and their relative genes in peripheral blood mononuclear cells from 73 patients with T2DM and 52 healthy donors by reverse transcription-quantitative polymerase chain reaction In addition, the association between miR-34a, miR-125b and their relevant genes expression profile were analyzed with respect to the pathogenesis of T2DM. The present study demonstrated that the expression levels of miR-125b and miR-34a were elevated in peripheral blood mononuclear cell samples from patients with T2DM. Furthermore, miR-34a and miR-125b were positively correlated with low-density lipoprotein/high-density lipoprotein (HDL) and Foxp3 and negatively related to triglyceride/HDL. However, no correlation among miR-34a, miR-125b and the value of homeostasis model assessment of insulin resistance, homeostasis model assessment of ß-cell function and the genes of B lymphocyte-induced maturation protein-1, interferon regulatory factor-4, P53 and retinoid-related orphan receptor γt were observed. These results indicate that the alteration of miR-34a and miR-125b exists in patients with T2DM, which may be involved in the pathogenesis of T2DM, and could be a potential novel biomarker of T2DM.

Brain-Derived Neurotrophic Factor Mediated Perfluorooctane Sulfonate Induced-Neurotoxicity via Epigenetics Regulation in SK-N-SH Cells.

Perfluorooctane sulfonate (PFOS), a new kind of persistent organic pollutant, is widely distributed in the environment and exists in various organisms, where it is also a neurotoxic compound. However, the potential mechanism of its neurotoxicity is still unclear. To examine the role of epigenetics in the neurotoxicity induced by PFOS, SK-N-SH cells were treated with different concentrations of PFOS or control medium (0.1% DMSO) for 48 h. The mRNA levels of DNA methyltransferases (DNMTs) and Brain-derived neurotrophic factor (BDNF), microRNA-16, microRNA-22, and microRNA-30a-5p were detected by Quantitative PCR (QPCR). Enzyme Linked Immunosorbent Assay (ELISA) was used to measure the protein levels of BDNF, and a western blot was applied to analyze the protein levels of DNMTs. Bisulfite sequencing PCR (BSP) was used to detect the methylation status of the BDNF promoter I and IV. Results of MTT assays indicated that treatment with PFOS could lead to a significant decrease of cell viability, and the treated cells became shrunk. In addition, PFOS exposure decreased the expression of BDNF at mRNA and protein levels, increased the expression of microRNA-16, microRNA-22, microRNA-30a-5p, and decreased the expression of DNMT1 at mRNA and protein levels, but increased the expression of DNMT3b at mRNA and protein levels. Our results also demonstrate that PFOS exposure changes the methylation status of BDNF promoter I and IV. The findings of the present study suggest that methylation regulation of BDNF gene promoter and increases of BDNF-related-microRNA might underlie the mechanisms of PFOS-induced neurotoxicity.

PFOS Disturbs BDNF-ERK-CREB Signalling in Association with Increased MicroRNA-22 in SH-SY5Y Cells.

Perfluorooctane sulfonate (PFOS), a ubiquitous environmental pollutant, is neurotoxic to mammalian species. However, the underlying mechanism of its neurotoxicity was unclear. We hypothesized that PFOS suppresses BDNF expression to produce its neurotoxic effects by inhibiting the ERK-CREB pathway. SH-SY5Y human neuroblastoma cells were exposed to various concentrations of PFOS to examine the role of the BDNF-ERK-CREB signalling pathway in PFOS-induced apoptosis and cytotoxicity. Furthermore, to ascertain the mechanism by which PFOS reduces BDNF signalling, we examined the expression levels of miR-16 and miR-22, which potentially regulate BDNF mRNA translation at the posttranscriptional level. Results indicated that PFOS significantly decreased cell viability and induced apoptosis in SH-SY5Y cells. In addition, BDNF and pERK protein levels decreased after PFOS treatment; however, pCREB protein levels were significantly elevated in PFOS treated groups. TrkB protein expression increased in the 10 µM and 50 µM PFOS groups and significantly decreased in the 100 µM PFOS group. Our results demonstrated that PFOS exposure decreased miR-16 expression and increased miR-22 expression, which may represent a possible mechanism by which PFOS decreases BDNF protein levels. PFOS may inhibit BDNF-ERK-CREB signalling by increasing miR-22 levels, which may, in part, explain the mechanism of PFOS neurotoxicity.