Sesamin alleviates lipid accumulation induced by oleic acid via PINK1/Parkin-mediated mitophagy in HepG2 cells.

Sesamin, a special compound present in sesame and sesame oil, has been reported a role in regulating lipid metabolism, while the underlying mechanisms remain unclear. Autophagy has been reported associated with lipid metabolism and regarded as a key modulator in liver steatosis. The present work aimed to investigate whether sesamin could exert its protective effects against lipid accumulation via modulating autophagy in HepG2 cells stimulated with oleic acid (OA). Cell viability was evaluated using the CCK-8 method, and triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein, cholesterol (LDL-C), alanine aminotransferase (ALT), along with aspartate aminotransferase (AST) were assessed by oil red O staining, transmission electron microscopy (TEM), and biochemical kits to investigate the lipid-lowering effects of sesamin. Differentially expressed genes were screened by RNA sequencing and validated using real-time quantitative PCR and Western blot. Autophagy and mitophagy related molecules were analyzed employing TEM, Western blot, and immunofluorescence. The data shows that in HepG2 cells stimulated by OA, sesamin reduces levels of TG, TC, LDL-C, ALT, and AST while elevating HDL-C, alleviates the lipid accumulation and improves fatty acid metabolism through modulating the levels of fat metabolism related genes including PCSK9, FABP1, CD36, and SOX4. Sesamin restores the suppressed autophagy in HepG2 cells caused by OA, which could be blocked by autophagy inhibitors. This indicates that sesamin improves fatty acid metabolism by enhancing autophagy levels, thereby mitigating the intracellular lipid accumulation. Furthermore, sesamin significantly enhances the mitophagy and improves mitochondrial homeostasis via activating the PINK/Parkin pathway. These data suggest that sesamin alleviates the excessive lipid accumulation in HepG2 caused by OA by restoring the impaired mitophagy via the PINK1/Parkin pathway, probably playing a preventive or therapeutic role in hepatic steatosis.

Corydalis tomentella Franch. Exerts anti-inflammatory and analgesic effects by regulating the calcium signaling pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Corydalis tomentella Franch. is a perennial cespitose plant commonly used to treat stomachaches as a folk medicine. The C. tomentella total alkaloids have good protective effects against acute liver injury and potential anti-hepatoma and anti-Alzheimer's disease activities. AIM OF THE STUDY: To establish an effective purification process for total alkaloids from C. tomentella and investigate the mechanism of their anti-inflammatory effects. MATERIALS AND METHODS: Corydalis tomentella were purified using macroporous resin. Then the crude and purified C. tomentella extracts (cCTE and pCTE) were qualitatively analyzed using UPLC-Triple-TOF-MS/MS. The cCTE and pCTE were used to investigate and compare their anti-inflammatory effects on lipopolysaccharide (LPS)-induced RAW264.7 cells. Doses at 100, 200 and 400 mg/kg/d of pCTE were used to study their anti-inflammatory and analgesic activities in mice with xylene-induced ear swelling and acetic acid-induced writhing tests. Content of nitric oxide (NO), interleukin-6 (IL-6), interleukin-1ß (IL-1ß), and tumor necrosis factor-α (TNF-α) were determined both in RAW264.7 cells and mice. Network pharmacology was used to predict the anti-inflammatory mechanism of C. tomentella, and the key enzymes were validated using qPCR and Western Blot analysis. Concentration of intracellular Ca2+ was detected using flow cytometric analysis. RESULTS: The C. tomentella total alkaloid purity increased from 6.29% to 47.34% under optimal purification conditions. A total of 54 alkaloids were identified from CTE. Both cCTE and pCTE could suppress the LPS-induced production of NO, IL-6, IL-1ß, and TNF-α in RAW264.7 cells. The pCTE exhibited a more potent anti-inflammatory effect; it also inhibited pain induced by xylene and acetic acid in mice. The calcium signaling pathway is associated with the anti-inflammatory and analgesic activities of C. tomentella. The mRNA expression of nitric oxide synthase (NOS) 2, NOS3 and calmodulin1 (CALM1) was regulated by C. tomentella through the reduction of inflammation-induced Ca2+ influx, and it also exhibited a more pronounced effect than the positive control (L-NG-nitro arginine methyl ester). CONCLUSIONS: Purified C. tomentella extract shows anti-inflammatory effect both in vitro and in vivo. It exerts anti-inflammatory and analgesic effects through the calcium signaling pathway by down-regulating NOS2 and CALM1 expression and up-regulating NOS3 expression in LPS-induced RAW264.7 cells, and decreasing intracellular Ca2+ concentration.

TIL-Derived CAR T Cells Improve Immune Cell Infiltration and Survival in the Treatment of CD19-Humanized Mouse Colorectal Cancer.

Chimeric antigen receptor-engineered T cells (CAR Ts) targeting CD19 have shown unprecedented prognosis in treating hematological cancers. However, the lack of a tumor-specific antigen as the target and an inhospitable tumor environment limit the clinical application of CAR T in solid tumors. Tumor-infiltrating T lymphocytes (TIL) exhibit diverse T cell receptor clonality and superior tumor-homing abilities. Therefore, in our study, human CD19-target TIL CAR-Ts armed with CD3ζ and 4-1BB signaling domains were constructed. Mouse colorectal cancer CT26 cells expressing human CD19 (hCD19+-CT26) were developed to assess the anti-tumor activity of TIL CAR-T cells, both in vitro and in vivo. Compared with splenic CAR T adoptive transfer, TIL CAR-T administration showed superior tumor suppression ability in hCD19+-CT26 tumor-bearing mice. Furthermore, more T cells were found at the tumor site and had lower exhaustion-related inhibitory receptor (T cell immunoglobulin and mucin domain-containing protein 3, Tim3) expression and higher immune memory molecule (CD62L) expression. Overall, we provided an artificial tumor-specific antigen in solid tumors and demonstrated that combined CAR-expressing TIL-Ts (TIL CAR-Ts) exhibited strong anti-tumor activity, with improved T cell infiltration and immune memory. Our humanized tumor antigen presented platform of mice suggests that TIL CAR-T-based adoptive therapy could be a promising strategy for solid cancer treatment.

Baicalin Attenuates H2O2-Induced Oxidative Stress by Regulating the AMPK/Nrf2 Signaling Pathway in IPEC-J2 Cells.

Oxidative stress can adversely affect the health status of the body, more specifically by causing intestinal damage by disrupting the permeability of the intestinal barrier. This is closely related to intestinal epithelial cell apoptosis caused by the mass production of reactive oxygen species (ROS). Baicalin (Bai) is a major active ingredient in Chinese traditional herbal medicine that has antioxidant, anti-inflammatory, and anti-cancer properties. The purpose of this study was to explore the underlying mechanisms by which Bai protects against hydrogen peroxide (H2O2)-induced intestinal injury in vitro. Our results indicated that H2O2 treatment caused injury to IPEC-J2 cells, resulting in their apoptosis. However, Bai treatment attenuated H2O2-induced IPEC-J2 cell damage by up-regulating the mRNA and protein expression of ZO-1, Occludin, and Claudin1. Besides, Bai treatment prevented H2O2-induced ROS and MDA production and increased the activities of antioxidant enzymes (SOD, CAT, and GSH-PX). Moreover, Bai treatment also attenuated H2O2-induced apoptosis in IPEC-J2 cells by down-regulating the mRNA expression of Caspase-3 and Caspase-9 and up-regulating the mRNA expression of FAS and Bax, which are involved in the inhibition of mitochondrial pathways. The expression of Nrf2 increased after treatment with H2O2, and Bai can alleviate this phenomenon. Meanwhile, Bai down-regulated the ratio of phosphorylated AMPK to unphosphorylated AMPK, which is indicative of the mRNA abundance of antioxidant-related genes. In addition, knockdown of AMPK by short-hairpin RNA (shRNA) significantly reduced the protein levels of AMPK and Nrf2, increased the percentage of apoptotic cells, and abrogated Bai-mediated protection against oxidative stress. Collectively, our results indicated that Bai attenuated H2O2-induced cell injury and apoptosis in IPEC-J2 cells through improving the antioxidant capacity through the inhibition of the oxidative stress-mediated AMPK/Nrf2 signaling pathway.

Low complexity domains of the nucleocapsid protein of SARS-CoV-2 form amyloid fibrils.

The self-assembly of the Nucleocapsid protein (NCAP) of SARS-CoV-2 is crucial for its function. Computational analysis of the amino acid sequence of NCAP reveals low-complexity domains (LCDs) akin to LCDs in other proteins known to self-assemble as phase separation droplets and amyloid fibrils. Previous reports have described NCAP's propensity to phase-separate. Here we show that the central LCD of NCAP is capable of both, phase separation and amyloid formation. Within this central LCD we identified three adhesive segments and determined the atomic structure of the fibrils formed by each. Those structures guided the design of G12, a peptide that interferes with the self-assembly of NCAP and demonstrates antiviral activity in SARS-CoV-2 infected cells. Our work, therefore, demonstrates the amyloid form of the central LCD of NCAP and suggests that amyloidogenic segments of NCAP could be targeted for drug development.

Blunting ROS/TRPML1 pathway protects AFB1-induced porcine intestinal epithelial cells apoptosis by restoring impaired autophagic flux.

Aflatoxin B1 (AFB1) is a stable mycotoxin that contaminates animal feed on a large scale and causes severe damage to intestinal cells, induces inflammation and stimulates autophagy. Transient receptor potential mucolipin subfamily 1 (TRPML1) is a regulatory factor of autophagy, but the underlying mechanisms of TRPML1-mediated autophagy in AFB1 intestine toxicity remain elucidated. In the present study, AFB1 (0, 5, 10 µg/mL) was shown to reduce cell viability, increase reactive oxygen species (ROS) accumulation and apoptosis rate. Additionally, AFB1 caused structural damage to mitochondria and lysosomes and increased autophagosomes numbers. Furthermore, AFB1 promoted Ca2+ release by activating the TRPML1 channel, stimulated the expression of autophagy-related proteins, and induced autophagic flux blockade. Moreover, pharmacological inhibition of autophagosome formation by 3-methyladenine attenuated AFB1-induced apoptosis by downregulating the levels of TRPML1 and ROS, whereas blockade of autophagosome-lysosomal fusion by chloroquine alleviated AFB1-induced apoptosis by upregulating TRPML1 expression and exacerbating ROS accumulation. Intriguingly, blocking AFB1-induced autophagic flux generated ROS- and TRPML1-dependent cell death, as shown by the decreased apoptosis in the presence the free radical scavenger N-Acetyl-L-cysteine and the TRPML1 inhibitor ML-SI1. Overall, these results showed that AFB1 promoted apoptosis of IPEC-J2 cells by disrupting autophagic flux through activation of the ROS/TRPML1 pathway.

Integrated Small Animal PET/CT/RT with Onboard PET/CT Image Guidance for Preclinical Radiation Oncology Research.

We have integrated a compact and lightweight PET with an existing CT image-guided small animal irradiator to enable practical onboard PET/CT image-guided preclinical radiation therapy (RT) research. The PET with a stationary and full-ring detectors has ~1.1 mm uniform spatial resolution over its imaging field-of-view of 8.0 cm diameter and 3.5 cm axial length and was mechanically installed inside the irradiator in a tandem configuration with CT and radiation unit. A common animal bed was used for acquiring sequential dual functional and anatomical images with independent PET and CT control and acquisition systems. The reconstructed dual images were co-registered based on standard multi-modality image calibration and registration processes. Phantom studies were conducted to evaluate the integrated system and dual imaging performance. The measured mean PET/CT image registration error was ~0.3 mm. With one-bed and three-bed acquisitions, initial tumor focused and whole-body [18F]FDG animal images were acquired to test the capability of onboard PET/CT image guidance for preclinical RT research. Overall, the results have shown that integrated PET/CT/RT can provide advantageous and practical onboard PET/CT image to significantly enhance the accuracy of tumor delineation and radiation targeting that should enhance the existing and enable new and potentially breakthrough preclinical RT research and applications.

Discovery of novel benzamide derivatives bearing benzamidophenyl and phenylacetamidophenyl scaffolds as potential antitumor agents via targeting PARP-1.

Poly(ADP-ribose) polymerase-1 (PARP-1) plays a crucial role in DNA damage repair and has been identified as a promising therapeutic target in cancer therapy. As a continuation of our efforts on the development of novel PARP-1 inhibitors with potent anticancer activity, a series of benzamide derivatives containing the benzamidophenyl and phenylacetamidophenyl scaffolds were designed and synthesized based on the structure optimization of our previously reported compound IX. All target compounds were screened for their in vitro antiproliferative activities against human colorectal cancer cells (HCT116, DLD-1 and SW480) and human normal colonic epithelial cells (NCM460). Among them, compound 13f exhibited the most potent anticancer activity against HCT116 cells and DLD-1 cells with IC50 = 0.30 µM and 2.83 µM, respectively. Moreover, 13f displayed significant selectivity in inhibiting HCT116 cancer cells over the normal NCM460 cells. Furthermore, 13f exhibited excellent PARP-1 inhibitory effect with IC50 = 0.25 nM. Besides, 13f was found to effectively inhibit colony formation and migration of HCT116 cells. Studies on the mechanisms revealed that 13f could arrest cell cycle at G2/M phase, accumulate DNA double-strand breaks, reduce mitochondrial membrane potential and ultimately induce apoptosis in HCT116 cells. In addition, molecular docking study indicated that 13f could combine firmly with the catalytic pocket of PARP-1 through multiple hydrogen bond interactions. Collectively, these findings demonstrated that 13f could serve as a promising anticancer candidate and deserves further investigation.

Chemical characterization and solvent fractionation of tilapia oil for its potential application as human milk fat substitute.

The natural source of human milk fat substitute (HMFS) is a field worth exploring. In this study, tilapia oil was extracted and analyzed. In the triacylglycerol fraction, the contents of sn-2 palmitic acid and total sn-1,3 oleic acid and linoleic acid were 48.01% and 66.62%, respectively. The optimal solvent fractionation conditions were determined to be a tilapia oil-to-acetone ratio of 1:8 (w/v), crystallization temperature of -30°C, and crystallization duration of 16 h, giving a solid fraction yield of 64.20%. In fractionated tilapia oil, the total content of 1-oleoyl-2-palmitoyl-3-linoleoylglycerol (OPL) and 1,3-dioleoyl-2-palmitoylglycerol (OPO) increased by 20.38%, as determined by reversed-phase liquid chromatography. Ultra-high-performance combined-phase chromatography combined with quadrupole time-of-flight mass spectrometry analysis showed that OPL (17.45%) was the most abundant triacylglycerol in fractionated tilapia oil, followed by OPO (13.90%). Fractionated tilapia oil is thus an excellent source of OPL and has great potential for incorporation in HMFS. PRACTICAL APPLICATION: Human milk fat substitutes are an important component of infant formulas. This work provides an excellent natural source of oil rich in OPL, which has great potential in the field of preparing human milk fat substitutes highly similar to human milk fat.

Design, synthesis, biological evaluation and molecular docking study of novel urea-based benzamide derivatives as potent poly(ADP-ribose) polymerase-1 (PARP-1) inhibitors.

Poly(ADP-ribose) polymerase-1 (PARP-1) is one of the key members of DNA repair enzymes that is responsible for the repair of DNA single-strand breaks. Inhibition of PARP-1 has been demonstrated to be a promising strategy to selectively kill tumor cells by targeting DNA repair pathway. Herein, a series of novel urea-based benzamide derivatives were designed and synthesized based on the structure-based drug design strategy. The anticancer activities against five human cancer cell lines including HCT116, MDA-MB-231, HeLa, A579 and A375 were evaluated and the preliminary structure-activity relationships were summarized. Among them, compounds 23f and 27f exhibited potent antiproliferative effects against HCT116 cells with IC50 values of 7.87 µM and 8.93 µM, respectively. Moreover, both compounds displayed excellent PARP-1 inhibitory activities with IC50 values of 5.17 nM and 6.06 nM, respectively. Mechanistic investigations showed that 23f and 27f could effectively inhibit colony formation and cell migration of HCT116 cells. Furthermore, 23f and 27f could cause cell cycle arrest at G2/M phase, and induce apoptosis by upregulating the expression of Bax and cleaved Caspase-3 and downregulating the expression of Caspase-3 and Bcl-2 in HCT116 cells. In addition, molecular docking studies provided the rational binding modes of these compounds in complex with PARP-1. Collectively, these results suggested that 23f and 27f could serve as promising drug candidates for further investigation.

Structure-based discovery of small molecules that disaggregate Alzheimer's disease tissue derived tau fibrils in vitro.

Alzheimer's disease (AD) is the consequence of neuronal death and brain atrophy associated with the aggregation of protein tau into fibrils. Thus disaggregation of tau fibrils could be a therapeutic approach to AD. The small molecule EGCG, abundant in green tea, has long been known to disaggregate tau and other amyloid fibrils, but EGCG has poor drug-like properties, failing to fully penetrate the brain. Here we have cryogenically trapped an intermediate of brain-extracted tau fibrils on the kinetic pathway to EGCG-induced disaggregation and have determined its cryoEM structure. The structure reveals that EGCG molecules stack in polar clefts between the paired helical protofilaments that pathologically define AD. Treating the EGCG binding position as a pharmacophore, we computationally screened thousands of drug-like compounds for compatibility for the pharmacophore, discovering several that experimentally disaggregate brain-derived tau fibrils in vitro. This work suggests the potential of structure-based, small-molecule drug discovery for amyloid diseases.

De novo designed protein inhibitors of amyloid aggregation and seeding.

Neurodegenerative diseases are characterized by the pathologic accumulation of aggregated proteins. Known as amyloid, these fibrillar aggregates include proteins such as tau and amyloid-ß (Aß) in Alzheimer's disease (AD) and alpha-synuclein (αSyn) in Parkinson's disease (PD). The development and spread of amyloid fibrils within the brain correlates with disease onset and progression, and inhibiting amyloid formation is a possible route toward therapeutic development. Recent advances have enabled the determination of amyloid fibril structures to atomic-level resolution, improving the possibility of structure-based inhibitor design. In this work, we use these amyloid structures to design inhibitors that bind to the ends of fibrils, "capping" them so as to prevent further growth. Using de novo protein design, we develop a library of miniprotein inhibitors of 35 to 48 residues that target the amyloid structures of tau, Aß, and αSyn. Biophysical characterization of top in silico designed inhibitors shows they form stable folds, have no sequence similarity to naturally occurring proteins, and specifically prevent the aggregation of their targeted amyloid-prone proteins in vitro. The inhibitors also prevent the seeded aggregation and toxicity of fibrils in cells. In vivo evaluation reveals their ability to reduce aggregation and rescue motor deficits in Caenorhabditis elegans models of PD and AD.

Real-time marker-less tumor tracking with TOF PET:in silicofeasibility study.

Purpose.Although positron emission tomography (PET) can provide a functional image of static tumors for RT guidance, it's conventionally very challenging for PET to track a moving tumor in real-time with a multiple frame/s sampling rate. In this study, we developed a novel method to enable PET based three-dimension (3D) real-time marker-less tumor tracking (RMTT) and demonstrated its feasibility with a simulation study.Methods.For each line-of-response (LOR) acquired, its positron-electron annihilation position is calculated based on the time difference between the two gamma interactions detected by the TOF PET detectors. The accumulation of these annihilation positions from data acquired within a single sampling frame forms a coarsely measured 3D distribution of positron-emitter radiotracer uptakes of the lung tumor and other organs and tissues (background). With clinically relevant tumor size and sufficient differential radiotracer uptake concentrations between the tumor and background, the high-uptake tumor can be differentiated from the surrounding low-uptake background in the measured distribution of radiotracer uptakes. With a volume-of-interest (VOI) that closely encloses the tumor, the count-weighted centroid of the annihilation positions within the VOI can be calculated as the tumor position. All these data processes can be conducted online. The feasibility of the new method was investigated with a simulated cardiac-torso digital phantom and stationary dual-panel TOF PET detectors to track a 28 mm diameter lung tumor with a 4:1 tumor-to-background18FDG activity concentration ratio.Results.The initial study shows TOF PET based RMTT can achieve <2.0 mm tumor tracking accuracy with 5 frame s-1sampling rate under the simulated conditions. In comparison, using reconstructed PET images to track a similar size tumor would require >30 s acquisition time to achieve the same tracking accuracy.Conclusion.With the demonstrated feasibility, the new method may enable TOF PET based RMTT for practical RT applications.

Molecular cloning, characterization, and expression analysis of TIPE1 in chicken (Gallus gallus): Its applications in fatty liver hemorrhagic syndrome.

Tumor necrosis factor-α-induced protein eight like 1 (TIPE1) plays important role in autophagy, immunity, and lipid metabolism. The potential role of TIPE1 in fatty liver hemorrhage syndrome (FLHS) is elusory. In the present study, the full-length coding sequence of TIPE1 was cloned, and the polyclonal antibody of TIPE1 was produced by the recombinant TIPE1 protein. The bioinformatic analysis showed that the chicken TIPE1 protein, which was predicted to be a hydrophobic and non-transmembrane protein without signal peptide was highly different from that of mammals. Furthermore, proceeded by using TIPE1 polyclonal antibody, the tissue distribution analysis showed that TIPE1 protein is ubiquitously expressed in various tissues in adult hens and chicks, with its level being higher in the liver and, spleen, moderate in intestinal, brain, and heart. Besides, immunohistochemistry and immunofluorescence observation demonstrated that TIPE1 mainly existed in the cytoplasm in liver, duodenum, and cecum cell. Notably, the TIPE1 expressions were significantly decreased in laying hens suffering from FLHS. Collectively, these results showed that the chicken TIPE1 polyclonal antibody was successfully prepared and further used to analyze the expression profiles of chicken. And the expression of TIPE1 was reduced in FLHS which provided the foundation for further investigation in FLHS.

Baicalin ameliorates APEC-induced intestinal injury in chicks by inhibiting the PI3K/AKT-mediated NF-κB signaling pathway.

Avian pathogenic Escherichia coli (APEC) is the causative agent of avian colibacillosis. Baicalin (BA) possesses multiple pharmacological effects, but the mechanism underlying its activity in APEC-induced intestinal injury remains unknown. This study aims to investigate the protective effects and possible mechanism of BA against APEC-induced intestinal injury. Sixty 1-day-old chicks were randomly divided into 4 groups: the control group (basal diet), E. coli group (basal diet), BAI10 group (10 mg/kg BA), and BAI20 group (20 mg/kg BA). After pretreatment with BA for 15 d and subsequent induction of APEC infection by pectoralis injection, the ileum was collected and analyzed. The results showed that BA-pretreatment demonstrated an alleviation of chicks in diarrhea rate, mortality, and histopathological changes in intestinal tissues after APEC infection. Additionally, following APEC infection, BA improved the intestinal barrier by elevating zona occludens (ZO)s (ZO-1, 2, 3), Claudins (Claudin1, 2, 3), Occludin, avian ß-defensin (AvBD)s (AvBD1, 2, 4), lysozyme (Lyz) mRNA levels and ZO-1, Claudin1, and Occludin protein levels. Besides, the activities of total superoxide dismutase (T-SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) and the SOD-1 and CAT mRNA levels and SOD-1 protein level were elevated by BA pretreatment. BA pretreatment also decreased the malondialdehyde (MDA) content, heme oxygenase-1 (HO-1) and NADH quinone oxidoreductase 1 (NQO1) mRNA levels, and HO-1 protein level after APEC infection. BA alleviated the APEC-induced inflammatory response, including downregulating the mRNA levels of proinflammatory cytokines (tumor necrosis factor-α (TNF-α), interleukin [IL]-1ß, IL-6, IL-8) and upregulating the mRNA levels of anti-inflammatory cytokines (IL-4, IL-10, IL-13, transforming growth factor-ß [TGF-ß]). Furthermore, BA decreased the mRNA and protein levels of phosphatidylinositol 3 kinase (PI3K), protein kinase B (AKT), and nuclear factor kappa-B (NF-κB) as well as the expression of the phosphorylated forms of these proteins after APEC infection. Collectively, our findings indicate that BA exerts a protective effect against APEC-induced intestinal injury in chicks by inhibiting the PI3K/AKT-mediated NF-κB pathway, suggesting that BA may be a potential therapeutic approach for avian colibacillosis.

A compact and lightweight small animal PET with uniform high-resolution for onboard PET/CT image-guided preclinical radiation oncology research.

OBJECTIVE: In contrast to clinical radiation therapy (RT) that ubiquitously uses PET/CT image to accurately guide RT, all current commercial animal irradiators can only provide CT image-guided preclinical RT that severely limits their capability for preclinical and compatibility for translational radiation oncology research. To address this problem, we have developed a compact and lightweight PET with uniform, high spatial resolution that is suited to be installed inside an existing animal irradiator for potential onboard PET/CT image-guided preclinical RT research. APPROACH: The design focused on the balance of achieving sufficient imaging performance for practical preclinical RT guidance with constrained size and weight. The detector head consists of a ring of 12 detector panels in a dodecagon configuration and 12 front-end electronics boards that are closely attached to the detector panels. The overall size and weight of the detector head are 33.0 cm diameter, 11.0 cm axial length and ∼6.5 kg weight that can be installed inside an existing irradiator. Each detector panel has a 30 × 30 array of 1 × 1 × 20 mm3LYSO scintillators with depth-of-interaction (DOI) measurement. The front-end electronics boards process and convert detected signals to digital signals and transfer them to system electronics and data acquisition located outside the irradiator through low-voltage-differential-signaling cables. MAIN RESULTS: The typical energy, DOI and coincidence timing resolutions are around 22.1%, 3.1 mm, and 1.92 ns. The imaging field-of-view (FOV) is 8.0 cm diameter and 3.5 cm axial length. The performance evaluations show a 1.8% sensitivity at the center FOV, uniform ∼1.1 mm resolution within 6 cm diameter FOV, and all rods of 1.0 mm diameter can be clearly resolved from the image of an ultra-micro hot-rods phantom. SIGNIFICANCE: Overall, this compact and lightweight PET has demonstrated its designed capability and performance sufficient for providing onboard functional/biological/molecular image to guide the preclinical RT research.

Oxygen-Sensitive MRI: A Predictive Imaging Biomarker for Tumor Radiation Response?

PURPOSE: To develop a noninvasive prognostic imaging biomarker related to hypoxia to predict SABR tumor control. METHODS AND MATERIALS: A total of 145 subcutaneous syngeneic Dunning prostate R3327-AT1 rat tumors were focally irradiated once using cone beam computed tomography guidance on a small animal irradiator at 225 kV. Various doses in the range of 0 to 100 Gy were administered, while rats breathed air or oxygen, and tumor control was assessed up to 200 days. Oxygen-sensitive magnetic resonance imaging (MRI) (T1-weighted, ΔR1, ΔR2*) was applied to 79 of these tumors at 4.7 T to assess response to an oxygen gas breathing challenge on the day before irradiation as a probe of tumor hypoxia. RESULTS: Increasing radiation dose in the range of 0 to 90 Gy enhanced tumor control of air-breathing rats with a TCD50 estimated at 59.6 ± 1.5 Gy. Control was significantly improved at some doses when rats breathed oxygen during irradiation (eg, 40 Gy; P < .05), and overall there was a modest left shift in the control curve: TCD50(oxygen) = 53.1 ± 3.1 Gy (P < .05 vs air). Oxygen-sensitive MRI showed variable response to oxygen gas breathing challenge; the magnitude of T1-weighted signal response (%ΔSI) allowed stratification of tumors in terms of local control at 40 Gy. Tumors showing %ΔSI >0.922 with O2-gas breathing challenge showed significantly better control at 40 Gy during irradiation while breathing oxygen (75% vs 0%, P < .01). In addition, increased radiation dose (50 Gy) substantially overcame resistance, with 50% control for poorly oxygenated tumors. Stratification of dose-response curves based on %ΔSI >0.922 revealed different survival curves, with TCD50 = 36.2 ± 3.2 Gy for tumors responsive to oxygen gas breathing challenge; this was significantly less than the 54.7 ± 2.4 Gy for unresponsive tumors (P < .005), irrespective of the gas inhaled during tumor irradiation. CONCLUSIONS: Oxygen-sensitive MRI allowed stratification of tumors in terms of local control at 40 Gy, indicating its use as a potential predictive imaging biomarker. Increasing dose to 50 Gy overcame radiation resistance attributable to hypoxia in 50% of tumors.

Individual and combined effects of frying load and deteriorated polar compounds on the foaming of edible oil.

Foaming of frying oil has troubled the production but not yet systematically explained. In this research, individual and combined effects of 16 process, chemical and physical parameters of frying oil were tested. Prepared oil samples with different deterioration levels were further physically blended to avoid the interference of colinearity. A new integrated index to describe the Molecular Weight Disparity (MWD) was proposed and proved to be well correlated with both deterioration and foaming of oil (r = 0.845 ~ 0.997, p < 0.05). Effects of all indices except the peroxide value, anisidine value, total oxidation value and surface tension of oil were significant (p < 0.05) and their combined effect was presented by equations (p < 0.05). The effect of frying load was approximately 1.3 times higher than that of oil deterioration. Data will be helpful to seek efficient oil formulation and achieve intelligent control of industrial production.

Urolithin B, a gut microbiota metabolite, protects against myocardial ischemia/reperfusion injury via p62/Keap1/Nrf2 signaling pathway.

Ischemia/reperfusion (IR) induces additional damage during the restoration of blood flow to ischemic myocardium. Urolithin B (UB) is one of the gut metabolites of ellagitannins, a class of antioxidant polyphenols, which was found to be protective against oxidative stress in multiple organs. However, the role of UB in cardiovascular disease remains elusive. Adult Sprague Dawley rats were subjected to left anterior descending artery ligation for 30 min followed by 120 min of reperfusion, with or without UB treatment. In vitro, the H9c2 cardiomyocytes were subjected to hypoxia (94 %N2/5 %CO2/1 %O2) for 3 h, followed by reoxygenation (74 %N2/5 %CO2/21 %O2) for 3 h (HR). UB was found to decrease myocardial infarct size and attenuate the cardiac dysfunction in the rats after IR, and protect against HR injury in H9c2 cardiomyocytes. Mechanistically, UB inhibited autophagy by activating Akt/mTOR/ULK1 pathway and protected against oxidative stress and caspase 3-dependent cell apoptosis. In particular, UB induced accumulation of p62 and its interaction with Keap1, which promoted Nrf2 nuclear translocation during HR insult. Of note, the protection of UB against superoxide production and apoptotic cell death was compromised with Nrf2 gene silencing. Taken together, our findings suggested that UB protected against myocardial IR injury at least partially via the p62/Keap1/Nrf2 signaling pathway, which highlights the potential of UB as a novel therapy for ischemic heart disease.

Novel On-line PET Imaging for Intra-Beam Range Verification and Delivery Optimization: A Simulation Feasibility Study.

On-line PET image-based method uses an initial particle beam to measure the particle beam range (BR) within the same fraction so that any measured range-shift with respect to the predicted BR can be compensated before the rest therapeutic beam deliveries. However, the method requires to use a low-dose initial beam to minimize the risk of beam overshooting, which leads to low image count and inaccurate BR measurement. In this in-silico study, we evaluated the feasibility of a new on-line PET imaging method that measures BR at the mid-plane of a target volume with part of the high-dose therapy beams to verify BR and guide adaptive treatment re-planning. Simulations included various processes of proton beam radiations to a tumor inside a human brain phantom, positron and PET image generation at the mid-plane with initial beams, activity range measurement, and range-shift compensated beam delivery. The results demonstrated that the new method, under the simulated conditions, can achieve ~1.1 mm mid-plane BR measurement accuracy and closely match the delivered range-shift compensated dose distribution with the planned one. Overall, it is promising that this new method may significantly improve particle therapy accuracy.