“D-cell hypothesis of schizophrenia”: Background theory of Novel non-D2 receptor medicinal chemistry

The latest psychopharmacological study showed effectiveness of a novel non-D2-receptor-binding drug, SEP-363856, for the treatment of schizophrenia. Characteristic receptor profile of the compound is shown to be trace amine-associated receptor 1 (TAAR1) full agonist and 5-hydroxytryptamin 1A (5-HT 1A) receptor partial agonist. I found the TAAR1 ligand neuron, D-neuron, in the striatum and nucleus accumbens (Acc), an antipsychotic acting site, of human brain, though failed to find in the homologous area of monkey. To study human D-neuron functions, total of 154 post-mortem brains, and a modified immunohistochemical method using high qualified antibodies against monoamine-related substances, was applied. Number of D-neurons in the caudate nucleus, putamen, and Acc was reduced in post-mortem brains with schizophrenia. The reduction was significant (p<0.05) in Acc. “D-cell hypothesis of schizophrenia”, which I proposed based on this post-mortem brain study, that NSC dysfunction-induced D-neuron reduction as cellular and molecular basis of mesolimbic dopamine (DA) hyperactivity, showing progressive pathophysiology of schizophrenia, has been proved to be a predictive hypothesis for TAAR1 medicinal chemistry.

D-neuron, ligand neuron of trace amine-associated receptor 1 (TAAR1): Key of novel non-D2 receptor-binding antipsychotics

The latest psychopharmacological study showed effectiveness of a novel non-D2-receptor-binding drug, SEP-363856, for the treatment of schizophrenia. The compound is trace amine-associated receptor 1 (TAAR1) full agonist and also 5-hydroxytryptamin 1A (5-HT 1A) receptor partial agonist. I found the TAAR1 ligand neuron, D-neuron, in the striatum and nucleus accumbens (Acc), a neuroleptic acting site, of human brains, though failed to find in the homologous area of monkey brains. To study human D-neuron functions, total of 154 post-mortem brains, and a modified immunohistochemical method using high qualified antibodies against monoamine-related substances, was applied. The number of D-neuron in the caudate nucleus, putamen, and Acc was reduced in post-mortem brains with schizophrenia. The reduction was significant (p<0.05) in Acc. I proposed “D-cell hypothesis of schizophrenia”, that NSC dysfunction-based D-neuron reduction is cellular and molecular basis of mesolimbic dopamine (DA) hyperactivity, progressive pathophysiology and prospectiveness of TAAR1 medicinal chemistry, emphasizing importance of D-neuron.

Recent discoveries of new Elephantomyia (Diptera, Limoniidae) fossils in Baltic amber

New data on the genus Elephantomyia (Diptera: Limoniidae) from Baltic amber are presented. A new subgenus Hoffeinsonia subgen. nov. is established with one new species: Elephantomyia (Hoffeinsonia) prima sp. nov. The new subgenus is characterized by a wing at most 2.5 × as long as it is wide without a darker pattern along the veins Sc and R1, elongate Sc, straight vein R1, sharp half of vein R2+3+4 sharply arched to the upper edge of the wing, short, wide, trapezoidal d-cell and oval pterostigma. The fossil subgenus Hoffeinsonia subgen. nov. shares features with the extant subgenera Elephantomyodes and Elephantomyia. One other extinct species of Elephantomyia was discovered and described herein as E. (s. str.) christelae sp. nov. Such features as a very elongate vein R2+3+4, 2.5 × as long as the Rs easily allowing this new species to be distinguished from the other fossil representatives of the genus Elephantomyia. The taxonomic decision on Elephantomyia grata as a species placed in nominative subgenus is provided. A list and key of fossil species of Elephantomyia are given. The morphological pattern of the genus is discussed in relation to the adaptation to a specific food spectrum, coevolution with Angiospermae of the representative genus Helius known since Cretaceous and closely related to this genus representatives of the much younger genus Elephantomyia.

Nanoparticle-Based Drug Delivery Systems for Photodynamic Therapy of Metastatic Melanoma: A Review

Metastatic melanoma (MM) is a skin malignancy arising from melanocytes, the incidence of which has been rising in recent years. It poses therapeutic challenges due to its resistance to chemotherapeutic drugs and radiation therapy. Photodynamic therapy (PDT) is an alternative non-invasive modality that requires a photosensitizer (PS), specific wavelength of light, and molecular oxygen. Several studies using conventional PSs have highlighted the need for improved PSs for PDT applications to achieve desired therapeutic outcomes. The incorporation of nanoparticles (NPs) and targeting moieties in PDT have appeared as a promising strategy to circumvent various drawbacks associated with non-specific toxicity, poor water solubility, and low bioavailability of the PSs at targeted tissues. Currently, most studies investigating new developments rely on two-dimensional (2-D) monocultures, which fail to accurately mimic tissue complexity. Therefore, three-dimensional (3-D) cell cultures are ideal models to resemble tumor tissue in terms of architectural and functional properties. This review examines various PS drugs, as well as passive and active targeted PS nanoparticle-mediated platforms for PDT treatment of MM on 2-D and 3-D models. The overall findings of this review concluded that very few PDT studies have been conducted within 3-D models using active PS nanoparticle-mediated platforms, and so require further investigation.

3-D Culture of Marine Sponge Cells for Production of Bioactive Compounds

Production of sponge-derived bioactive compounds in vitro has been proposed as an alternative to wild harvest, aquaculture, and chemical synthesis to meet the demands of clinical drug development and manufacture. Until recently, this was not possible because there were no marine invertebrate cell lines. Recent breakthroughs in the development of sponge cell lines and rapid cell division in improved nutrient media now make this approach a viable option. We hypothesized that three-dimensional (3-D) cell cultures would better represent how sponges function in nature, including the production of bioactive compounds. We successfully cultured sponge cells in 3-D matrices using FibraCel® disks, thin hydrogel layers, and gel microdroplets (GMDs). For in vitro production of bioactive compounds, the use of GMDs is recommended. Nutrients and sponge products rapidly diffuse into and out of the 3-D matrix, the GMDs may be scaled up in spinner flasks, and cells and/or secreted products can be easily recovered. Research on scale-up and production is in progress in our laboratory.

Abstract 27: Unravelling Cell-specific Interactions At The Preeclamptic Maternal-foetal Interface From Early To Late Pregnancy

Preeclamptic syndrome arrises in the fetal part of the placenta (villi). In this study, we analyse placental development by single nuclei RNA-sequencing in early and term pregnancy and draw conclusions about pathological processes in preeclampsia (PE) that originate early in gestation. We profiled the transcriptome of 101,067 nuclei obtained from a total of 12 pregnancies, spanning early, term and PE doners. Using unsupervised computational approaches, we identified 12 and 16 different cell types and states in decidua and villi, respectively. Our comprehensively identified catalogue of cell types and states aligns well with the previous single cell studies. We identified different subpopulations of syncytiotrophoblast and GATA3+/GREM2+ trophoblast stem cells (TSC) in villi. Through gestation, gene expression in cell populations from the matrisome or vascular environments show dynamic expression reflecting vascular development associated with spiral artery remodelling and concordant decidual stroma reorganisation. Global differential gene expression analysis shows that trophoblast cell types are most dysregulated in PE. Cell-cell communication analysis revealed important dysregulation between villi and decidual cell types. The secretory signalling characteristic of this trophoblastic disease may be used for early biomarker screening. Overall, this study paves the way to a deeper understanding of the early pathophysiology of PE. Figure 1: Villi (v) and decidua (d) cell clusters from early, late control and preeclampsia (PE) villi and decidua visualised as a UMAP. Datasets were integrated separately for each tissue and merged for embedding.

A comprehensive study on 2D, 3D and solid tumor environment to explore a multifunctional biogenic nanoconjugate

Emergence of nanotechnology created a drastic change in the field of cancer therapy due to their unique features in drug delivery and imaging. Polysaccharide based nanoparticles have received extensive attention in recent years as promising nanoparticle mediated drug delivery systems. Polysaccharides are endorsed with versatile merits including high drug encapsulation efficiency, efficient drug protection against chemical or enzymatic degradation, unique ability to create a controlled release and cellular internalization. In the current study, we have fabricated doxorubicin-loaded carboxymethylated PST001 coated iron oxide nanoparticles (DOX@CM-PST-IONPs) for better management of cancer. CM-PST coated iron oxide nanoparticles co-encapsulated with chemotherapeutic drug doxorubicin, can be utilized for targeted drug delivery. Biocompatible and non-toxic nanoconjugates was found to be effective in both 2-D and 3-D cell culture system with efficient cancer cell internalization. The bench-marked potential of CM-PIONPs to produce reactive oxygen species makes it a noticeable drug delivery system to compact neoplasia. These nanoconjugates can lay concrete on a better way for the elimination of cancer spheroids and tumor burden.