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Background: Alcohol use disorders affect millions of people worldwide, and there is growing evidence that excessive alcohol intake causes severe damage to the brain of both humans and animals. Numerous studies on chronic alcohol exposure in animal models have identified that many functional impairments are associated with the hippocampus, which is a structure exhibiting substantial vulnerability to alcohol exposure. However, the precise mechanisms that lead to structural and functional impairments of the hippocampus are poorly understood. Herein, we report a novel cell death type, namely pyroptosis, which accounts for alcohol neurotoxicity in mice. Methods: For this study, we used an in vivo model to induce alcohol‐related neurotoxicity in the hippocampus. Adult male C57BL/6 mice were treated with 95% alcohol vapor either alone or in combination with selective cannabinoid receptor antagonists or agonists, and VX765 (Belnacasan), which is a selective caspase‐1 inhibitor. Results: Alcohol‐induced in vivo pyroptosis occurs because of an increase in the levels of pyroptotic proteins such as nucleotide‐binding domain (NOD)–like receptor protein 3 (NLRP3), caspase‐1, gasdermin D (GSDMD), and amplified inflammatory response. Our results indicated that VX765 suppressed the expression of caspase‐1 and inhibited the maturation of the proinflammatory cytokines interleukin‐1β (IL‐1β) and IL‐18. Additionally, chronic alcohol intake created an imbalance in the endocannabinoid system and regulated 2 cannabinoid receptors (CB1R and CB2R) in the hippocampus. Specific antagonists of CB1R (AM251 and AM281) significantly ameliorated alcohol‐induced pyroptosis signaling and inactivated the inflammatory response. Conclusions: Alcohol induces hippocampal pyroptosis, which leads to neurotoxicity, thereby indicating that pyroptosis may be an essential pathway involved in chronic alcohol–induced hippocampal neurotoxicity. Furthermore, cannabinoid receptors are regulated during this process, which suggests promising therapeutic strategies against alcohol‐induced neurotoxicity through pharmacologic inhibition of CB1R. [ABSTRACT FROM AUTHOR]

BACKGROUND: The pathogenesis of osteoarthritis is unknown, and there is no effective treatment. Selecting appropriate animal models will create a good condition for animal experiments on osteoarthritis. OBJECTIVE: To review different experimental animals of osteoarthritis and different modeling methods. METHODS: CNKI, WanFang, VIP and PubMed databases were searched for the articles published from January 2013 to July 2018. The keywords were 'osteoarthritis, models, animals, mice, rats, goats, guinea pigs, sheep" in Chinese and English, respectively. The repetitive articles were excluded, and the articles related to osteoarthritis and animal models were selected for summary and result analysis. RESULTS AND CONCLUSION: Mice, rats, guinea pigs, rabbits, dogs, sheep and other animals can be used as animal models for osteoarthritis research. When studying animal models of osteoarthritis, it is important to choose the right animal models and construction methods. Non-surgical models will not make damage to the parts except for joints, which is in accordance with the pathological process of osteoarthritis. But it is difficult to control, thus causing errors, and it cannot simulate traumatic changes. Surgical models induce joint injury by tissue damage, which exhibits advantages in rapid disease progress and obvious outcomes. Therefore, surgical models are optimal choice for short-term experiments. Different experimental animals and modeling schemes have their own advantages and disadvantages, which need to be reasonably selected according to the requirements of experiments. [ABSTRACT FROM AUTHOR]

Aims Alcohol abuse has attracted public attention and chronic alcohol exposure can result in irreversible structural changes in the brain. The molecular mechanisms underlying alcohol neurotoxicity are complex, mandating comprehensive mining of spatial protein expression profile. Methods In this study, mice models of chronic alcohol intoxication were established after 95% alcohol vapor administration for 30 consecutive days. On Day 30, striatum (the dorsal and ventral striatum) and hippocampus, the two major brain regions responsible for learning and memorizing while being sensitive to alcohol toxicity, were collected. After that, isobaric tags for relative and absolute quantitation -based quantitative proteomic analysis were carried out for further exploration of the novel mechanisms underlying alcohol neurotoxicity. Results Proteomic results showed that in the striatum, 29 proteins were significantly up-regulated and 17 proteins were significantly down-regulated. In the hippocampus, 72 proteins were significantly up-regulated, while 2 proteins were significantly down-regulated. Analysis of the overlay proteins revealed that a total of 102 proteins were consistently altered (P  < 0.05) in both hippocampus and striatum regions, including multiple keratins such as Krt6a, Krt17 and Krt5. Ingenuity pathway analysis revealed that previously reported diseases/biofunctions such as dermatological diseases and developmental disorders were enriched in those proteins. Interestingly, the glucocorticoid receptor (GR) signaling was among the top enriched pathways in both brain regions, while multiple keratins from the GR signaling such as Krt1 and Krt17 exhibited significantly opposite expression patterns in the two brain nuclei. Moreover, there are several other involved pathways significantly differed between the hippocampus and striatum. Conclusions Our data revealed brain regional differences upon alcohol consumption and indicated the critical involvement of keratins from GR signaling in alcohol neurotoxicity. The differences in proteomic results between the striatum and hippocampus suggested a necessity of taking into consideration brain regional differences and intertwined signaling pathways rather than merely focusing on single nuclei or molecule during the study of drug-induced neurotoxicity in the future. [ABSTRACT FROM AUTHOR]

Fracture healing is a complex process of many coordinated biological pathways. This system can go awry resulting in nonunion, which leads to significant patient morbidity. The Hedgehog (Hh) signaling pathway is upregulated in fracture healing. We hypothesized that the Hh signaling pathway can be pharmacologically modulated to positively affect fracture healing. Diaphyseal femur fractures were created in elderly mice (18 months, C57BL/6 females), which have a blunted and delayed healing response compared to younger mice, and were stabilized with intramedullary pins. To activate the Hh pathway we targeted the receptor Smoothened using an agonist (Hh‐Ag1.5 [Hh‐Ag]) and compared this to a vehicle control. Expression of Hh target genes were significantly increased in the fracture callus of the agonist group compared to controls, indicating pathway activation. Expression of osteogenic and chondrogenic‐related genes was greatly upregulated in fracture callus versus intact femora, although Hh agonist treatment did not consistently enhance this response. Blindly graded, radiographic callus healing scores were significantly higher in the Hh‐Ag groups at post operative day (POD) 14, indicating earlier callus bridging. On microCT, Hh‐Ag treatment led to greater callus volume (+40%) and bone volume (+25%) at POD21. By day 14, callus vascularity, as assessed by 3D microCT angiography vessel volume, was 85% greater in the Hh‐Ag group. Finally, mechanical strength of the calluses in the Hh‐Ag groups was significantly greater than in the control groups at POD21. In conclusion, systemic administration of a Hh agonist appears to improve the osseous and vascular healing responses in a mouse fracture healing‐impaired model. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res [ABSTRACT FROM AUTHOR]

Background: Until recently, the mechanism for the malignant hyperthermia crisis has been attributed solely to sustained massive Ca release from the sarcoplasmic reticulum on exposure to triggering agents. This study tested the hypothesis that transient receptor potential cation (TRPC) channels are important contributors to the Ca dyshomeostasis in a mouse model relevant to malignant hyperthermia.Methods: This study examined the mechanisms responsible for Ca dyshomeostasis in RYR1-p.G2435R mouse muscles and muscle cells using calcium and sodium ion selective microelectrodes, manganese quench of Fura2 fluorescence, and Western blots.Results: RYR1-p.G2435R mouse muscle cells have chronically elevated intracellular resting calcium and sodium and rate of manganese quench (homozygous greater than heterozygous) compared with wild-type muscles. After exposure to 1-oleoyl-2-acetyl-sn-glycerol, a TRPC3/6 activator, increases in intracellular resting calcium/sodium were significantly greater in RYR1-p.G2435R muscles (from 153 ± 11 nM/10 ± 0.5 mM to 304 ± 45 nM/14.2 ± 0.7 mM in heterozygotes P < 0.001] and from 251 ± 25 nM/13.9 ± 0.5 mM to 534 ± 64 nM/20.9 ± 1.5 mM in homozygotes [P < 0.001] compared with 123 ± 3 nM/8 ± 0.1 mM to 196 ± 27 nM/9.4 ± 0.7 mM in wild type). These increases were inhibited both by simply removing extracellular Ca and by exposure to either a nonspecific (gadolinium) or a newly available, more specific pharmacologic agent (SAR7334) to block TRPC6- and TRPC3-mediated cation influx into cells. Furthermore, local pretreatment with SAR7334 partially decreased the elevation of intracellular resting calcium that is seen in RYR1-p.G2435R muscles during exposure to halothane. Western blot analysis showed that expression of TRPC3 and TRPC6 were significantly increased in RYR1-p.G2435R muscles in a gene-dose-dependent manner, supporting their being a primary molecular basis for increased sarcolemmal cation influx.Conclusions: Muscle cells in knock-in mice expressing the RYR1-p.G2435R mutation are hypersensitive to TRPC3/6 activators. This hypersensitivity can be negated with pharmacologic agents that block TRPC3/6 activity. This reinforces the working hypothesis that transient receptor potential cation channels play a critical role in causing intracellular calcium and sodium overload in malignant hyperthermia-susceptible muscle, both at rest and during the malignant hyperthermia crisis. [ABSTRACT FROM AUTHOR]

Our previous studies have shown that a rat insulin promoter II fragment (RIP) was used to effectively target pancreatic adenocarcinoma (PDAC) and insulinoma that over-express pancreatic and duodenal homeobox-1 (PDX-1). To enhance the activity and specificity of the human insulin promoter, we engineered a synthetic human insulin super-promoter (SHIP). Reporter assay demonstrated that SHIP1 was the most powerful promoter among all of the SHIPs and had far greater activity than the endogenous human insulin promoters and RIP in PDAC expressing PDX-1. Over-expression, knockdown and competitive inhibition of PDX-1 expression assay proved that PDX-1 is a critical transcript factor to regulate the activity of SHIP1. SHIP1-driven viral thymidine kinase followed by ganciclovir (SHIP1-TK/GCV) resulted in cytotoxicity to PDAC cells in vitro. Systemic delivery of SHIP1-TK/GCV in PDAC xenograft mice significantly suppressed PANC-1 tumor growth in vivo greater than RIP-TK/GCV and CMV-TK/GCV controls (p < .05). These preclinical data suggest that SHIP1 is a powerful novel promoter that can be used to target human PDAC expressing PDX-1 in clinical trials. Furthermore, this novel strategy of engineering synthetic super-promoters could be used for other cancer targets. [ABSTRACT FROM AUTHOR]