Project description:MicroRNAs (miRNAs) are important in the regulation of many biological processes including muscle development. However, little is known regarding miRNA regulation of muscle regeneration. In mature murine tibialis anterior muscle following injury, 298 miRNAs were significantly changed during the time course of muscle regeneration including 86 that were altered greater than 10-fold as compared to uninjured muscle. Temporal miRNA expression patterns were identified and included inflammation-related miRNAs (miR-223 and -147) that increased immediately after injury; this pattern contrasted to that of mature muscle-specific miRNAs (miR-1, -133a and -499) that were abruptly decreased following injury and then up-regulated in later regenerative events. Another cluster of miRNAs were transiently increased in the early days of muscle regeneration. This included miR-351, a miRNA that was also transiently expressed during myogenic progenitor cell (MPC) differentiation in vitro. Based on computational predictions, further studies demonstrated that E2f3 was a target of miR-351 in myoblasts. Moreover, knockdown of miR-351 expression inhibited MPC proliferation and promoted apoptosis during MPC differentiation, whereas miR-351 overexpression protected MPC from apoptosis during differentiation. Collectively, these observations suggest that miR-351 is involved in both the maintenance of MPC proliferation and the transition of MPC into differentiated myotubes. Thus, a novel, time-dependent sequence of molecular events during skeletal muscle regeneration has been identified, i.e., miR-351 inhibits E2f3 expression, a key regulator of cell cycle progression and proliferation, and promotes MPC proliferation and protects early differentiating MPC from apoptosis, important events in the hostile tissue environment after acute muscle injury. Skeletal muscles are damaged and repaired repeatedly throughout life. Muscle regeneration maintains locomotor function during aging and delays the appearance of clinical symptoms in neuromuscular diseases, such as Duchenne muscular dystrophy. The capacity for skeletal muscle growth and regeneration is conferred by satellite cells located between the basal lamina and the sarcolemma of mature myofibers. Upon injury, satellite cells reenter the cell cycle, proliferate, and then exit the cell cycle either to renew the quiescent satellite cell pool or to differentiate into mature myofibers. Despite recent advances, genes involved in these processes are still largely unknown. Understanding the molecular mechanisms that regulate satellite cell activities could promote development of novel countermeasures to enhance muscle regeneration that is compromised by diseases or aging. Using a muscle injury mouse model, we profiled miRNA expression during muscle regeneration.

Project description:Traditional Chinese Medicine (TCM) has been used for thousands of years to treat or prevent diseases, including cancer. Good manufacturing practices (GMP) and sophisticated product analysis (PhytomicsQC) to ensure consistency are now available allowing the assessment of its utility. Polychemical Medicines, like TCM, include chemicals with distinct tissue-dependent pharmacodynamic properties that result in tissue-specific bioactivity. Determining the mode of action of these mixtures was previously unsatisfactory; however, information rich RNA microarray technologies now allow for thorough mechanistic studies about complex mixtures effects. PHY906 is a long used four herb TCM formula employed as adjuvant to relieve side effects associated with chemotherapy. Animal studies documented a decrease in global toxicity and an increase in therapeutic effectiveness of chemotherapy when PHY906 was combined. Using a systems biology approach, we studied tumor tissue to identify reasons for the enhancement of the antitumor effect of Irinotecan by PHY-906 in a well-characterized pre-clinical model; PHY-906 and Irinotecan were administered orally to female BDF-1 mice bearing subcutaneous Colon 38 tumors. We observed that 1) individually PHY-906 and Irinotecan induce distinct alterations in tumor, liver and spleen; 2) PHY-906 alone predominantly induces repression of transcription and immune-suppression in tumors; 3) these effects are reverted in the presence of Irinotecan, with prevalent induction of pro-apoptotic and pro-inflammatory pathways that may favor tumor rejection. Most importantly, PHY-906 together with Irinotecan triggers unique changes not activated by each one alone suggesting that the combination creates a unique tissue-specific response. Four groups of BDF-1 mice bearing colon 38 tumors were treated with Phosphate Buffered Saline (PBS) (n=10), PHY-906 (n=10), Irinotecan (CPT-11, Camptosar(TM)) (n=10) or the combination PHY-906 and Irinotecan (n=10). Tumor (38 samples), spleen (38 samples), and liver (35 samples) tissues were removed and frozen for total RNA isolation and subsequent microarray hybridization. There were a total of 111 samples representing 12 treated tissue groups with 8 to 10 biological replicates each. A reference sample was generated from a pool of mixed normal mouse tissue.

Project description:Inflammatory Bowel Disease (IBD) is a term describing a collection of conditions characterised by chronic inflammatory disorder of the gastrointestinal tract involving an inappropriate immune response to commensal microorganisms in a genetically susceptible host. Four kiwifruit extracts, aqueous and ethyl acetate extracts of gold kiwifruit (Actinidia chinensis) or green kiwifruit (A. deliciosa), have previously demonstrated anti-inflammatory activity using in vitro models of IBD. This study examined whether these kiwifruit extracts had immune modulating effects in vivo against inflammatory processes known to be increased in patients with IBD. KFEs were used as a dietary intervention in Il10-/- mice (an in vivo model of IBD) and the C57BL/6J background strain in a 3 x 2 factorial design. While all Il10-/- mice developed significant colonic inflammation compared to the C57BL/6J mice, this was not affected by the inclusion of KFE in the diet. Whole genome gene and protein expression level profiling indicated that KFEs influenced immune signalling pathways and metabolic processes within the colonic tissue; however, the effects were subtle. In particular, adaptive immune pathways were reduced by three out of four kiwifruit extracts, with greater reduction seen in the C57BL/6J mice. This suggests that while immune-modulating activity was present in vivo, KFEs did not reduce inflammatory processes relevant to IBD. Experimental design. Two experiments were conducted, one using extracts from gold kiwifruit and one using extracts from green kiwifruit. Within each experiment, both Il10-/- and C57 mice were randomly divided into three diet treatment groups, to ive the following 12 treatments: 1) Gold Kiwifruit Experiment, C57BL/6J mice, Control diet (AIN-76A), 2) Gold Kiwifruit Experiment, C57BL/6J mice, Aqueous Kiwifruit Extract Supplemented Diet (AIN-76A + 5% Aqueous KFE) 3) Gold Kiwifruit Experiment, C57BL/6J mice, Ethyl Acetate Kiwifruit Extract Supplemented Diet (AIN-76A + 0.11% Ethyl Acetate KFE) 4) Gold Kiwifruit Experiment, Il10-/- mice, Control diet (AIN-76A), 5) Gold Kiwifruit Experiment, Il10-/- mice, Aqueous Kiwifruit Extract Supplemented Diet (AIN-76A + 5% Aqueous KFE) 6) Gold Kiwifruit Experiment, Il10-/- mice, Ethyl Acetate Kiwifruit Extract Supplemented Diet (AIN-76A + 0.11% Ethyl Acetate KFE) 7) Green Kiwifruit Experiment, C57BL/6J mice, Control diet (AIN-76A), 8) Green Kiwifruit Experiment, C57BL/6J mice, Aqueous Kiwifruit Extract Supplemented Diet (AIN-76A + 5% Aqueous KFE) 9) Green Kiwifruit Experiment, C57BL/6J mice, Ethyl Acetate Kiwifruit Extract Supplemented Diet (AIN-76A + 0.11% Ethyl Acetate KFE) 10) Green Kiwifruit Experiment, Il10-/- mice, Control diet (AIN-76A), 11) Green Kiwifruit Experiment, Il10-/- mice, Aqueous Kiwifruit Extract Supplemented Diet (AIN-76A + 5% Aqueous KFE) 12) Green Kiwifruit Experiment, Il10-/- mice, Ethyl Acetate Kiwifruit Extract Supplemented Diet (AIN-76A + 0.11% Ethyl Acetate KFE) Six biological replicates were analysed from each treatment group, except for groups 3 and 7 where five replicates were analysed due to array quality issues with the sixth replicate. Each replicate contained mRNA from one mouse. A reference design was used, where each slide was hybridised with mRNA from one sample (green channel) and mRNA from a common reference pool (red channel).

Dataset Information

Transcription profiling of mouse tumor cell lines responses to caffeine treatment

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure