Identification of an HLA-A*11:01-restricted neoepitope of mutant PIK3CA and its specific T cell receptors for cancer immunotherapy targeting hotspot driver mutations.

Hotspot driver mutations presented by human leukocyte antigens might be recognized by anti-tumor T cells. Based on their advantages of tumor-specificity and immunogenicity, neoantigens derived from hotspot mutations, such as PIK3CAH1047L, may serve as emerging targets for cancer immunotherapies. NetMHCpan V4.1 was utilized for predicting neoepitopes of PIK3CA hotspot mutation. Using in vitro stimulation, antigen-specific T cells targeting the HLA-A*11:01-restricted PIK3CA mutation were isolated from healthy donor-derived peripheral blood mononuclear cells. T cell receptors (TCRs) were cloned using single-cell PCR and sequencing. Their functionality was assessed through T cell activation markers, cytokine production and cytotoxic response to cancer cell lines pulsed with peptides or transduced genes of mutant PIK3CA. Immunogenic mutant antigens from PIK3CA and their corresponding CD8+ T cells were identified. These PIK3CA mutation-specific CD8+ T cells were subsequently enriched, and their TCRs were isolated. The TCR clones exhibited mutation-specific and HLA-restricted reactivity, demonstrating varying degrees of functional avidity. Identified TCR genes were transferred into CD8+ Jurkat cells and primary T cells deficient of endogenous TCRs. TCR-expressing cells demonstrated specific recognition and reactivity against the PIK3CAH1047L peptide presented by HLA-A*11:01-expressing K562 cells. Furthermore, mutation-specific TCR-T cells demonstrated an elevation in cytokine production and profound cytotoxic effects against HLA-A*11:01+ malignant cell lines harboring PIK3CAH1047L. Our data demonstrate the immunogenicity of an HLA-A*11:01-restricted PIK3CA hotspot mutation and its targeting therapeutic potential, together with promising candidates of TCR-T cell therapy.

Cbl-b inhibition promotes less differentiated phenotypes of T cells with enhanced cytokine production.

For adoptive therapy with T cell receptor engineered T (TCR-T) cells, the quantity and quality of the final cell product directly affect their anti-tumor efficacy. The post-transfer efficacy window of TCR-T cells is keen to optimizing attempts during the manufacturing process. Cbl-b is a E3 ubiquitin ligase previously shown with critical negative impact in T cell functions. This study investigated whether strategic inclusion of a commercially available small inhibitor targeting Cbl-b (Cbl-b-IN-1) prior to T cell activation could enhance the quality of the final TCR-T cell product. Examination with both PBMCs and TCR-T cells revealed that Cbl-b-IN-1 treatment promoted TCR expression efficiency, T cell proliferation potential and, specifically, cell survival capability post antigenic stimulation. Cbl-b-IN-1 exposure facilitated T cells in maintaining less differentiated states with enhanced cytokine production. Further, we found that Cbl-b-IN-1 effectively augmented the activation of TCR signaling, shown by increased phosphorylation levels of Zeta-chain-associated protein kinase 70 (ZAP70) and phospholipase c-γ1 (PLCγ1). In conclusion, our results evidence that the inclusion of Cbl-b inhibitor immediately prior to TCR-T cell activation may enhance their proliferation, survival, and function potentials, presenting an applicable optimization strategy for immunotherapy with adoptive cell transfer.

Glial growth factor 2 treatment alleviates ischemia and reperfusion-damaged integrity of the blood-brain barrier through decreasing Mfsd2a/caveolin-1-mediated transcellular and Pdlim5/YAP/TAZ-mediated paracellular permeability.

The impairment of blood-brain barrier (BBB) integrity is the pathological basis of hemorrhage transformation and vasogenic edema following thrombolysis and endovascular therapy. There is no approved drug in the clinic to reduce BBB damage after acute ischemic stroke (AIS). Glial growth factor 2 (GGF2), a recombinant version of neuregulin-1ß that can stimulates glial cell proliferation and differentiation, has been shown to alleviate free radical release from activated microglial cells. We previously found that activated microglia and proinflammatory factors could disrupt BBB after AIS. In this study we investigated the effects of GGF2 on AIS-induced BBB damage as well as the underlying mechanisms. Mouse middle cerebral artery occlusion model was established: mice received a 90-min ischemia and 22.5 h reperfusion (I/R), and were treated with GGF2 (2.5, 12.5, 50 ng/kg, i.v.) before the reperfusion. We showed that GGF2 treatment dose-dependently decreased I/R-induced BBB damage detected by Evans blue (EB) and immunoglobulin G (IgG) leakage, and tight junction protein occludin degradation. In addition, we found that GGF2 dose-dependently reversed AIS-induced upregulation of vesicular transcytosis increase, caveolin-1 (Cav-1) as well as downregulation of major facilitator superfamily domain containing 2a (Mfsd2a). Moreover, GGF2 decreased I/R-induced upregulation of PDZ and LIM domain protein 5 (Pdlim5), an adaptor protein that played an important role in BBB damage after AIS. In addition, GGF2 significantly alleviated I/R-induced reduction of YAP and TAZ, microglial cell activation and upregulation of inflammatory factors. Together, these results demonstrate that GGF2 treatment alleviates the I/R-compromised integrity of BBB by inhibiting Mfsd2a/Cav-1-mediated transcellular permeability and Pdlim5/YAP/TAZ-mediated paracellular permeability.

A common whole-genome paleotetraploidization in Cucurbitales.

Cucurbitales are an important order of flowering plants known for encompassing edible plants of economic and medicinal value and numerous ornamental plants of horticultural value. By reanalyzing the genomes of two representative families (Cucurbitaceae and Begoniaceae) in Cucurbitales, we found that the previously identified Cucurbitaceae common paleotetraploidization that occurred shortly after the core-eudicot-common hexaploidization event is shared by Cucurbitales, including Begoniaceae. We built a multigenome alignment framework for Cucurbitales by identifying orthologs and paralogs and systematically redating key evolutionary events in Cucurbitales. Notably, characterizing the gene retention levels and genomic fractionation patterns between subgenomes generated from different polyploidizations in Cucurbitales suggested the autopolyploid nature of the Begoniaceae common tetraploidization and the allopolyploid nature of the Cucurbitales common tetraploidization and the Cucurbita-specific tetraploidization. Moreover, we constructed the ancestral Cucurbitales karyotype comprising 17 proto-chromosomes, confirming that the most recent common ancestor of Cucurbitaceae contained 15 proto-chromosomes and rejecting the previous hypothesis for an ancestral Cucurbitaceae karyotype with 12 proto-chromosomes. In addition, we found that the polyploidization and tandem duplication events promoted the expansion of gene families involved in the cucurbitacin biosynthesis pathway; however, gene loss and chromosomal rearrangements likely limited the expansion of these gene families.

A Systematic Stereo Camera Calibration Strategy: Leveraging Latin Hypercube Sampling and 2k Full-Factorial Design of Experiment Methods.

This research aimed to optimize the camera calibration process by identifying the optimal distance and angle for capturing checkered board images, with a specific focus on understanding the factors that influence the reprojection error (ϵRP). The objective was to improve calibration efficiency by exploring the impacts of distance and orientation factors and the feasibility of independently manipulating these factors. The study employed Zhang's camera calibration method, along with the 2k full-factorial analysis method and the Latin Hypercube Sampling (LHS) method, to identify the optimal calibration parameters. Three calibration methods were devised: calibration with distance factors (D, H, V), orientation factors (R, P, Y), and the combined two influential factors from both sets of factors. The calibration study was carried out with three different stereo cameras. The results indicate that D is the most influential factor, while H and V are nearly equally influential for method A; P and R are the two most influential orientation factors for method B. Compared to Zhang's method alone, on average, methods A, B, and C reduce ϵRP by 25%, 24%, and 34%, respectively. However, method C requires about 10% more calibration images than methods A and B combined. For applications where lower value of ϵRP is required, method C is recommended. This study provides valuable insights into the factors affecting ϵRP in calibration processes. The proposed methods can be used to improve the calibration accuracy for stereo cameras for the applications in object detection and ranging. The findings expand our understanding of camera calibration, particularly the influence of distance and orientation factors, making significant contributions to camera calibration procedures.

Alginate Oligosaccharides Repair Liver Injury by Improving Anti-Inflammatory Capacity in a Busulfan-Induced Mouse Model.

Liver diseases are associated with many factors, including medicines and alcoholics, which have become a global problem. It is crucial to overcome this problem. Liver diseases always come with inflammatory complications, which might be a potential target to deal with this issue. Alginate oligosaccharides (AOS) have been demonstrated to have many beneficial effects, especially anti-inflammation. In this study, 40 mg/kg body weight (BW) of busulfan was intraperitoneally injected once, and then the mice were dosed with ddH2O or AOS 10 mg/kg BW every day by oral gavage for five weeks. We investigated AOS as a potential no-side-effect and low-cost therapy for liver diseases. For the first time, we discovered that AOS 10 mg/kg recovered liver injury by decreasing the inflammation-related factors. Moreover, AOS 10 mg/kg could improve the blood metabolites related to immune and anti-tumor effects, and thus, ameliorated impaired liver function. The results indicate that AOS may be a potential therapy to deal with liver damage, especially in inflammatory conditions.

MXene-Regulated Metal-Oxide Interfaces with Modified Intermediate Configurations Realizing Nearly 100% CO2 Electrocatalytic Conversion.

Electrocatalytic CO2 reduction via renewable electricity provides a sustainable way to produce valued chemicals, while it suffers from low activity and selectivity. Herein, we constructed a novel catalyst with unique Ti3 C2 Tx MXene-regulated Ag-ZnO interfaces, undercoordinated surface sites, as well as mesoporous nanostructures. The designed Ag-ZnO/Ti3 C2 Tx catalyst achieves an outstanding CO2 conversion performance of a nearly 100% CO Faraday efficiency with high partial current density of 22.59 mA cm-2 at -0.87 V versus reversible hydrogen electrode. The electronic donation of Ag and up-shifted d-band center relative to Fermi level within MXene-regulated Ag-ZnO interfaces contributes the high selectivity of CO. The CO2 conversion is highly correlated with the dominated linear-bonded CO intermediate confirmed by in situ infrared spectroscopy. This work enlightens the rational design of unique metal-oxide interfaces with the regulation of MXene for high-performance electrocatalysis beyond CO2 reduction.

Paclitaxel-based supramolecular hydrogel loaded with mifepristone for the inhibition of breast cancer metastasis.

Breast cancer is the leading cause of cancer death among women and almost all of the breast cancer-caused mortality is related to metastasis. It has been reported that glucocorticoid facilitates the metastasis of breast cancer in mice, and mifepristone can antagonize the effect of glucocorticoid. Paclitaxel is one of the important drugs in the treatment of breast cancer. Mifepristone combined with paclitaxel could be an effective strategy for inhibiting breast cancer metastasis. However, their inherent defects, in terms of short blood circulation half-life and lack of tumor targeting, not only limit their effectiveness but also cause adverse reactions. Therefore, our aim is to explore a novel protocol against breast cancer metastasis, further optimize its therapeutic efficacy by a nanodelivery system, and explore its mechanism. Herein, a paclitaxel-conjugated and mifepristone-loaded hydrogel (PM-nano) was prepared by self-assembly. Its characterizations were studied. The antimetastatic effect was evaluated in vitro and in vivo and its mechanism was also explored by western blot assay. The resultant PM-nano was developed with favorable water solubility and good biocompatibility. Moreover, PM-nano displayed increased cell uptake properties and stimulated drug release in the tumor micro-acidic environment. The PM-nano was more effective in inhibiting the proliferation and metastasis of breast cancer than other groups in vitro and in vivo. The PM-nano might inhibit metastasis through glucocorticoid receptor/receptor tyrosine kinase-like orphan receptor 1 and MMPs. Taken together, PM-nano showed superior antimetastatic effects against breast cancer and excellent biocompatibility in vitro and in vivo, providing a new option for limiting metastasis.

Gut microbiota-testis axis: FMT improves systemic and testicular micro-environment to increase semen quality in type 1 diabetes.

BACKGROUND: Clinical data suggest that male reproductive dysfunction especially infertility is a critical issue for type 1 diabetic patient (T1D) because most of them are at the reproductive age. Gut dysbiosis is involved in T1D related male infertility. However, the improved gut microbiota can be used to boost spermatogenesis and male fertility in T1D remains incompletely understood. METHODS: T1D was established in ICR (CD1) mice with streptozotocin. Alginate oligosaccharide (AOS) improved gut microbiota (fecal microbiota transplantation (FMT) from AOS improved gut microbiota; A10-FMT) was transplanted into the T1D mice by oral administration. Semen quality, gut microbiota, blood metabolism, liver, and spleen tissues were determined to investigate the beneficial effects of A10-FMT on spermatogenesis and underlying mechanisms. RESULTS: We found that A10-FMT significantly decreased blood glucose and glycogen, and increased semen quality in streptozotocin-induced T1D subjects. A10-FMT improved T1D-disturbed gut microbiota, especially the increase in small intestinal lactobacillus, and blood and testicular metabolome to produce n-3 polyunsaturated fatty acid (PUFA) docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) to ameliorate spermatogenesis and semen quality. Moreover, A10-FMT can improve spleen and liver functions to strengthen the systemic environment for sperm development. FMT from gut microbiota of control animals (Con-FMT) produced some beneficial effects; however, to a smaller extent. CONCLUSIONS: AOS-improved gut microbiota (specific microbes) may serve as a novel, promising therapeutic approach for the improvement of semen quality and male fertility in T1D patients via gut microbiota-testis axis.

PACTS-Assisted Thermal Proteome Profiling for Use in Identifying Peptide-Interacting Proteins.

Bioactive peptides play important roles in various biological processes. However, the traditional methods for profiling the peptide-interacting proteins require modifications to the peptide molecules, often leading to false identifications. We found that the interaction between peptide ligands and protein receptors induced significant changes in the abundance of the interacting proteins, which is a signature indicating the interaction and providing complementary information for use in the classical thermal proteome profiling (TPP) technique. Herein, we developed a novel Peptide-ligand-induced Abundance Change of proTeinS (PACTS)-assisted TPP strategy for the identification of peptide-interacting proteins based on the peptide-ligand-induced change in protein abundance. The utility and efficacy of this approach were demonstrated by the identification of the interaction of the protein 3-phosphoinositide-dependent protein kinase 1 (PDPK1) and PDPK1-interacting fragment (PIF) pair and by large-scale profiling of the interacting proteins of PIF. The PACTS-assisted TPP approach was applied to describe the interactome of amyloid beta (Aß) 1-42 in THP-1 cells and resulted in the identification of 103 interacting proteins. Validation experiments indicated that Aß1-42 interacted directly with fatty acid synthase and inhibited its enzymatic activity, providing insights into fatty acid metabolic disorders in Alzheimer's disease (AD). Overall, PACTS-assisted TPP is an efficient approach, and the newly identified Aß-interacting proteins provide rich resources for the research on AD.

Conversion between duplicated genes generated by polyploidization contributes to the divergence of poplar and willow.

BACKGROUND: Gene conversion has an important effect on duplicate genes produced by polyploidization. Poplar (Populus trichocarpa) and willow (Salix brachista) are leading models and excellent green plants in the Salicaceae. Although much attention has been paid to the evolution of duplicated genes in poplar and willow, the role of conversion between duplicates generated from polyploidization remains poorly understood. RESULTS: Here, through genomic synteny analyses, we identified duplicate genes generated by the Salicaceae common tetraploidization (SCT) in the poplar and willow genomes. We estimated that at least 0.58% and 0.25% of poplar and willow duplicates were affected by whole-gene conversion after the poplar-willow divergence, with more (5.73% and 2.66%) affected by partial-gene conversion. Moreover, we found that the converted duplicated genes were unevenly distributed on each chromosome in the two genomes, and the well-preserved homoeologous chromosome regions may facilitate the conversion of duplicates. Notably, we found that conversion maintained the similarity of duplicates, likely contributing to the conservation of certain sequences, but is essentially accelerated the rate of evolution and increased species divergence. In addition, we found that converted duplicates tended to have more similar expression patterns than nonconverted duplicates. We found that genes associated with multigene families were preferentially converted. We also found that the genes encoding conserved structural domains associated with specific traits exhibited a high frequency of conversion. CONCLUSIONS: Extensive conversion between duplicate genes generated from the SCT contributes to the diversification of the family Salicaceae and has had long-lasting effects on those genes with important biological functions.

Ginkgolide B improved postoperative cognitive dysfunction by inhibiting microgliosis-mediated neuroinflammation in the hippocampus of mice.

BACKGROUND: Postoperative cognitive dysfunction (POCD) are a common complication of the central nervous system following surgery and anesthesia. The specific pathogenesis and effective therapeutics of POCD need to be further studied. Ginkgolide B (GB), a platelet-activating factor receptor-specific antagonist, has been suggested to have strong anti-inflammatory effects. Here we tested the effects and mechanism of GB on POCD of aged rats. METHODS: Neurobehavioral tests were used to investigate the effect of GB pretreatment on POCD. The hippocampus were harvested to test the expression of proinflammatory cytokines by ELISA. The expression of the microglial marker ionized calcium-binding adaptor molecule-1 (Iba-1) in the hippocampus was evaluated by western blot assay and immunohistochemistry. A Nissl staining experiment was used to detect the neuronal numbers in the hippocampus. RESULTS: Surgery might result in the overexpression of platelet activating factor (PAF) in the plasma and hippocampus and might cause hippocampus-dependent memory impairment. GB pretreatment, inhibited the activation of microglia, reduced the levels of IL-1ß and TNF-α, decreased the loss of neurons after surgery, and prevented POCD in aged rats. CONCLUSION: Our findings suggested that PAF was involved in the development of POCD. Improvement of POCD by PAF antagonist GB was associated with the inhibition of microgliosis-mediated neuroinflammation and neuronal apoptosis in aged rats.

Dual-Active Sites Engineering of N-Doped Hollow Carbon Nanocubes Confining Bimetal Alloys as Bifunctional Oxygen Electrocatalysts for Flexible Metal-Air Batteries.

Since the sluggish kinetic process of oxygen reduction (ORR)/evolution (OER) reactions, the design of highly-efficient, robust, and cost-effective catalysts for flexible metal-air batteries is desired but challenging. Herein, bimetallic nanoparticles encapsulated in the N-doped hollow carbon nanocubes (e.g., FeCo-NPs/NC, FeNi-NPs/NC, and CoNi-NPs/NC) are rationally designed via a general heat-treatment strategy of introducing NH3 pyrolysis of dopamine-coated metal-organic frameworks. Impressively, the resultant FeCo-NPs/NC hybrid exhibits superior bifunctional electrocatalytic performance for ORR/OER, manifesting exceptional discharging performance, outstanding lifespan, and prime flexibility for both Zn/Al-air batteries, superior to those of state-of-the-art Pt/C and RuO2 catalysts. X-ray absorption near edge structure and density functional theory indicate that the strong synergy between FeCo alloy and N-doped carbon frameworks has a distinctive activation effect on bimetallic Fe/Co atoms to synchronously modify the electronic structure and afford abundant dual-active Fe/Co-Nx sites, large surface area, high nitrogen doping level, and conductive carbon frameworks to boost the reversible oxygen electrocatalysis. Such N-doped carbon with bimetallic alloy bonds provides new pathways for the rational creation of high-efficiency energy conversion and storage equipment.

High-yield production of L-valine in engineered Escherichia coli by a novel two-stage fermentation.

L-valine is an essential amino acid and an important amino acid in the food and feed industry. The relatively low titer and low fermentation yield currently limit the large-scale application of L-valine. Here, we constructed a chromosomally engineered Escherichia coli to efficiently produce L-valine. First, the synthetic pathway of L-valine was enhanced by heterologous introduction of a feedback-resistant acetolactate acid synthase from Bacillus subtilis and overexpression of other two enzymes in the L-valine synthetic pathway. For efficient efflux of L-valine, an exporter from Corynebacterium glutamicum was subsequently introduced. Next, the precursor pyruvate pool was increased by knockout of GTP pyrophosphokinase and introduction of a ppGpp 3'-pyrophosphohydrolase mutant to facilitate the glucose uptake process. Finally, in order to improve the redox cofactor balance, acetohydroxy acid isomeroreductase was replaced by a NADH-preferring mutant, and branched-chain amino acid aminotransferase was replaced by leucine dehydrogenase from Bacillus subtilis. Redox cofactor balance enabled the strain to synthesize L-valine under oxygen-limiting condition, significantly increasing the yield in the presence of glucose. Two-stage fed-batch fermentation of the final strain in a 5 L bioreactor produced 84 g/L L-valine with a yield and productivity of 0.41 g/g glucose and 2.33 g/L/h, respectively. To the best of our knowledge, this is the highest L-valine titer and yield ever reported in E. coli. The systems metabolic engineering strategy described here will be useful for future engineering of E. coli strains for the industrial production of L-valine and related products.

Efficient synthesis of SCF3-substituted tryptanthrins by a radical tandem cyclization.

Herein, we report a new, efficient and atom-economical strategy for the synthesis of SCF3-substituted tryptanthrin derivatives. These previously unreported derivatives were obtained by means of a radical tandem cyclization. The reaction was triggered by addition of a SCF3 radical to a carbon-carbon double bond and involved the formation of a C(sp3)-SCF3 bond, a C(sp2)-C bond, and a C(sp2)-N bond. This method has mild conditions and a wide range of substrates which is particularly useful for the preparation of substituted indolquinazoline derivatives that widely exist in many natural products, but are not easy to obtain by conventional approaches.

Photoredox-Mediated Minisci C-H Alkylation Reactions between N-Heteroarenes and Alkyl Iodides with Peroxyacetate as a Radical Relay Initiator.

We developed a protocol for photoredox-mediated Minisci C-H alkylation reactions of N-heteroarenes in which readily available tert-butyl peroxyacetate acts as a radical relay precursor to generate alkyl radicals from alkyl iodides. This mild protocol tolerated a broad range of functional groups and could therefore be used for late-stage functionalization of complex nitrogen-containing natural products and drugs. Remarkably, by adopting a polarity-reversal strategy, we accomplished reactions that brought together an electron-deficient radical, a heteroarene to add alkene by means of a three-component radical relay process.

NIS-mediated oxidative arene C(sp2)-H amidation toward 3,4-dihydro-2(1H)-quinolinone, phenanthridone, and N-fused spirolactam derivatives.

A new radical-mediated intramolecular arene C(sp2)-H amidation of 3-phenylpropanamides or [1,1'-biphenyl]-2-carboxamides was developed to prepare a series of 3,4-dihydro-2(1H)-quinolinone and phenanthridone derivatives in moderate to excellent yields (33-94%). Spirolactams could also be obtained using this protocol.

Ti-Ti σ bond at oxygen vacancy inducing the deep defect level in anatase TiO2 (101) surface.

Using the GW method within many-body perturbation theory, we investigate the quasiparticle structures of defects, including oxygen vacancy, Ti interstitial, and hydroxyl groups, in the anatase TiO2 (101) surface. We find that the deep defect state in this surface observed experimentally, which is 1 eV below the Fermi level, originates from the σ bond formed between 3d orbitals of the two under-coordinated Ti atoms at the surface oxygen vacancy. Different from the density functional theory modified with on-site Coulomb terms (DFT + U), the GW method predicts that the localized polaron in anatase (101) is a shallow defect state close to the conduction band bottom. Polaronic states play the role in pinning the Fermi level of anatase near the conduction band bottom. Our GW calculations can explain satisfactorily the coexistence of shallow and deep defect states in anatase as observed in experiments. We also find that the conduction band edge of anatase is drawn down greatly after the filling of original empty Ti 3d orbitals by excess electrons, making the calculated bandgap of the reduced anatase agree well with the experiments. This significant difference in the bandgap between the intact and the reduced anatase is missed in DFT + U.

Unfolded protein response is involved in geniposide-regulating glucose-stimulated insulin secretion in INS-1 cells.

The growing evidence shows that in the early stage of type 2 diabetes mellitus (T2DM) development, when challenged by hyperglycemia and/or insulin resistance, pancreatic islets would produce more insulin to maintain the balance of blood sugar, but at the same time, endoplasmic reticulum (ER) stress will be initiated for the reason of over-compensation, which might be a crucial caused factor of dysfunction and death of pancreatic beta cell. In this study, we showed that high glucose induced a remarkably unfolded protein response (UPR) with the phosphorylation of PERK/eIF2α and IRE1α in INS-1 cells, but geniposide prevented the role of high glucose on the phosphorylation of PERK/eIF2α and IRE1α, respectively. Although inhibition of Txnip expression by siRNA had no significant effect on geniposide-regulating UPR, PERK and IRE1α were associated with geniposide-regulating Txnip degradation and glucose-stimulated insulin secretion (GSIS) in high glucose-cultured INS-1 cells. All these data suggest that geniposide might be an important regulator of ER stress and GSIS, and a promising compound for the treatment of T2DM. SIGNIFICANCE OF THE STUDY: Mounting evidence indicates that endoplasmic reticulum (ER) stress plays an essential role to maintain the normal cellular functions and dysfunction. In this study, we revealed that geniposide might be an important regulator of ER stress and glucose-stimulated insulin secretion in pancreatic beta cells.

miR-15b negatively correlates with lipid metabolism in mammary epithelial cells.

Mammary epithelial cells are regulated by steroid hormones, growth factors, and even microRNAs. miR-15b has been found to regulate lipid metabolism in adipocytes; however, its effects on lipid metabolism in mammary epithelial cells, the cells of lipid synthesis and secretion, are as yet unknown. The main purpose of this investigation was to explore the effect of miR-15b on lipid metabolism in mammary epithelial cells, along with the underlying mechanisms. miR-15b was overexpressed or inhibited by miRNA mimics or inhibitors; subsequently, lipid formation in mammary epithelial cells, and proteins related to lipid metabolism, were investigated. Through overexpression or inhibition of miR-15b expression, the current investigation found that miR-15b downregulates lipid metabolism in mammary epithelial cells and is expressed differentially at various stages of mouse and goat mammary gland development. Inhibition of miR-15b expression increased lipid content in mammary epithelial cells through elevation of the lipid synthesis enzyme fatty acid synthetase (FASN), and overexpression of miR-15b reduced lipid content in mammary epithelial cells with decreasing levels of FASN. Moreover, the steroid hormones estradiol and progesterone decreased miR-15b expression with a subsequent increase in lipid formation in mammary epithelial cells. The expression of miR-15b was lower during lactation and negatively correlated with lipid synthesis proteins, which suggests that it may be involved in lipid synthesis and milk production. miR-15b might be a useful target for altering lipid production and milk yield.