Comparative analysis of basal locomotor activity-related metabolic phenotypes between C57BL/6 mice and ICR mice substrains derived from three different sources

Current Advances in Cellular Approaches for Pathophysiology and Treatment of Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a prevalent gynecological and endocrine disorder that results in irregular menstruation, incomplete follicular development, disrupted ovulation, and reduced fertility rates among affected women of reproductive age. While these symptoms can be managed through appropriate medication and lifestyle interventions, both etiology and treatment options remain limited. Here we provide a comprehensive overview of the latest advancements in cellular approaches utilized for investigating the pathophysiology of PCOS through in vitro cell models, to avoid the confounding systemic effects such as in vitro fertilization (IVF) therapy. The primary objective is to enhance the understanding of abnormalities in PCOS-associated folliculogenesis, particularly focusing on the aberrant roles of granulosa cells and other relevant cell types. Furthermore, this article encompasses analyses of the mechanisms and signaling pathways, microRNA expression and target genes altered in PCOS, and explores the pharmacological approaches considered as potential treatments. By summarizing the aforementioned key findings, this article not only allows us to appreciate the value of using in vitro cell models, but also provides guidance for selecting suitable research models to facilitate the identification of potential treatments and understand the pathophysiology of PCOS at the cellular level.

SOCS3 Protein Mediates the Therapeutic Efficacy of Mesenchymal Stem Cells against Acute Lung Injury

Mesenchymal stem cells (MSCs) have been studied as novel therapeutic agents because of their immunomodulatory properties in inflammatory diseases. The suppressor of cytokine signaling (SOCS) proteins are key regulators of the immune response and macrophage modulation. In the present study, we hypothesized that SOCS in MCSs might mediate macrophage modulation and tested this in a bacteria-induced acute lung injury (ALI) mouse model. The macrophage phenotype was observed in RAW264.7 alveolar macrophages exposed to lipopolysaccharide (LPS) in an in vitro model, and in the ALI mouse model induced by tracheal administration of Escherichia coli (1 × 10⁷ CFU in 0.05mL PBS). In LPS-exposed RAW264.7 cells, the levels of markers of M1 macrophages, such as CD86 and pro-inflammatory cytokines (IL-1α, IL-1β, IL-6 and TNF-α), significantly increased, but they significantly reduced after MSC treatment. Meanwhile, the levels of markers of M2 macrophages, such as CD204 and anti-inflammatory cytokines (IL-4 and IL-10), increased after LPS exposure, and further significantly increased after MSC treatment. This regulatory effect of MSCs on M1/M2 macrophage polarization was significantly abolished by SOCS3 inhibition. In the E. coli-induced ALI model, tissue injury and inflammation in the mouse lung were significantly attenuated by the transplantation of MSCs, but not by SOCS3-inhibited MSCs. The regulatory effect of MSCs on M1/M2 macrophage polarization was observed in the lung injury model but was significantly abolished by SOCS3 inhibition. Taken together, our findings suggest that SOCS3 is an important mediator for macrophage modulation in anti-inflammatory properties of MSCs.

Physicochemical and Biochemical Evaluation of Amorphous Solid Dispersion of Naringenin Prepared Using Hot-Melt Extrusion

Naringenin (NRG) is a plant-derived flavonoid. Due to its antioxidant, anti-inflammatory, and analgesic activities it is beneficial to human health and is often used as a functional food ingredient; however, it has poor water solubility and low in vivo bioavailability. Therefore, the efficacy of NRG can be improved by enhancing its water solubility to increase gastrointestinal absorption. Conventional methods for the formulation of NRG are very complex and use toxic organic solvents, making them impractical for the production of functional foods. The objective of this study was to develop a safe and effective NRG-based functional food material. Previously, we established a technology to prepare amorphous solid dispersions (SDs) from functional food ingredients with poor water solubility and used hot-melt extrusion technology that is comparatively simple and does not involve the use of organic solvents. In this study, we prepared NRG SD and evaluated them both physicochemically and biochemically. NRG SD had superior water solubility and gastrointestinal absorption relative to native NRG and showed higher analgesic efficacy in rats than crystalline NRG. NRG SD was administered to mice in a mixed diet for 28 days, and organ weights and hematological/clinical biochemical parameters were assessed. NRG SD did not demonstrate severe adverse effects. The results suggest that NRG SD is a safe and highly efficacious formulation that can be used as a functional food material in the future.

Comparison of intrinsic exercise capacity and response to acute exercise in ICR (Institute of Cancer Research) mice derived from three different lineages

BACKGROUND

As a laboratory animal resource, the ICR mouse is commonly used in a variety of research fields. However, information on differences in exercise-related characteristics in ICR mice derived from different lineages and the underlying mechanisms remains to be elucidated. In this study, we investigated the intrinsic exercise capacity and a magnitude of response to acute exercise, and sought to identify mechanisms contributing to difference in Korl:ICR (a novel ICR lineage recently established by the National Institute of Food and Drug Safety Evaluation, Korea) and two commercialized ICR lineages derived from different origins (viz., A:ICR mouse from Orient Bio Com, the United States, and B:ICR mouse from Japan SLC Inc., Japan).

RESULTS

Results showed that despite no significant difference in body weight and weight-proportioned tissue mass of heart and skeletal muscles among groups, the relatively low intrinsic exercise capacity and exaggerated response to acute exercise were identified in B:ICR comparted with Korl:ICR and A:ICR, as reflected by total work and lactate threshold (LT). Also, the mitochondrial efficiency expressed as the complex 1 and complex 1 + 2 respiratory control ratio (RCR) values for cardiac mitochondrial O₂ consumption in B:ICR was significantly lower than that in Korl:ICR with higher level of state 2 respiration by glutamate/malate and UCP3 expression in cardiac muscle.

CONCLUSIONS

Taken together, these results indicate that the intrinsic exercise capacity of ICR mouse varies according to lineages, suggesting the role of cardiac mitochondrial coupling efficiency as a possible mechanism that might contribute to differences in the intrinsic exercise capacity and magnitude of response to exercise.

Inflammatory responses of C57BL/6NKorl mice to dextran sulfate sodium-induced colitis: comparison between three C57BL/6 N sub-strains

Background

Inflammatory bowel disease (IBD), including both Crohn’s disease and ulcerative colitis, are chronic human diseases that are challenging to cure and are often unable to be resolved. The inbred mouse strain C57BL/6 N has been used in investigations of IBD as an experimental animal model. The purpose of the current study was to compare the inflammatory responsiveness of C57BL/6NKorl mice, a sub-strain recently established by the National Institute of Food and Drug Safety Evaluation (NIFDS), with those of C57BL/6 N mice from two different sources using a dextran sulfate sodium (DSS)-induced colitis model.

Results

Male mice (8 weeks old) were administered DSS (0, 1, 2, or 3%) in drinking water for 7 days. DSS significantly decreased body weight and colon length and increased the colon weight-to-length ratio. Moreover, severe colitis-related clinical signs including diarrhea and rectal bleeding were observed beginning on day 4 in mice administered DSS at a concentration of 3%. DSS led to edema, epithelial layer disruption, inflammatory cell infiltration, and cytokine induction (tumor necrosis factor-α, interleukin-6, and interleukin-1β) in the colon tissues. However, no significant differences in DSS-promoted abnormal symptoms or their severity were found between the three sub-strains.

Conclusions

These results indicate that C57BL/6NKorl mice responded to DSS-induced colitis similar to the generally used C57BL6/N mice, thus this newly developed mouse sub-strain provides a useful animal model of IBD.

Taurine Stimulates Thermoregulatory Genes in Brown Fat Tissue and Muscle without an Influence on Inguinal White Fat Tissue in a High-Fat Diet-Induced Obese Mouse Model

This study was conducted to investigate if taurine supplementation stimulates the induction of thermogenic genes in fat tissues and muscles and decipher the mechanism by which taurine exerts its anti-obesity effect in a mildly obese ICR (CD-1®) mouse model. Three groups of ICR mice were fed a normal chow diet, a high-fat diet (HFD), or HFD supplemented with 2% taurine in drinking water for 28 weeks. The expression profiles of various genes were analyzed by real time PCR in interscapular brown adipose tissue (BAT), inguinal white adipose tissue (iWAT), and the quadriceps muscles of the experimental groups. Genes that are known to regulate thermogenesis like PGC-1α, UCP-1, Cox7a1, Cox8b, CIDE-A, and β1-, β2-, and β3-adrenergic receptors (β-ARs) were found to be differentially expressed in the three tissues. These genes were expressed at a very low level in iWAT as compared to BAT and muscle. Whereas, HFD increased the expression of these genes. Taurine supplementation stimulated the expression of UCP-1, Cox7a1, and Cox8b in BAT and only Cox7a1 in muscle, while there was a decrease in iWAT. In contrast, fat deposition-related genes, monoamine oxidases (MAO)-A, and -B, and lipin-1, were decreased by taurine supplementation only in iWAT and not in BAT or muscle. In conclusion, the potential anti-obesity effects of taurine may be partly due to upregulated thermogenesis in BAT, energy metabolism of muscle, and downregulated fat deposition in iWAT.

Comparative analysis of dose-dependent neurotoxic response to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine in C57BL/6 N mice derived from three different sources

MPTP, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine is commonly used to induce nigrostriatal defects to induce parkinsonism and/or parkinsonian syndrome, to replicate the lesions seen in Parkinson’s disease (PD), with use in numerous PD models in mice. It has been suggested that various biological characteristics including strain could result in differing mortality rates, sensitivity to MPTP administration, and reproducibility of lesions in mice, but there is no evidence on the sensitivity of C57BL/6 mice from different origins to MPTP and its associated pathological lesions. In this study, we investigated the magnitude of the dose-dependent response to acute MPTP administration in C57BL/6NKorl mice and two commercialized C57BL/6 stocks derived from the United States and Japan. We measured biological features (body weight, temperature, and composition), nigrostriatal neurotoxic responses (dopamine levels, tyrosine hydroxylase enzymes, and protein carbonylation) and motor function. In results, the three different C57BL/6 stocks exhibited similar overall neurotoxic response and locomotor impairment which increased in a dose-dependent manner with acute MPTP administration (10 mg/kg, 20 mg/kg, and 30 mg/kg, all with external heat support), although some of these differences were not significant. In conclusion, this study provides scientific evidence that C57BL/6NKorl mice can be used as an alternative animal model for practical and targeted PD research.