Optimization of adipogenic differentiation conditions for canine adipose-derived stem cells

The obesogen bisphenol A promotes adipogenesis in canine adipose-derived stem cells: Potential implication in dog obesity

The growing number of companion dogs has contributed to a rapidly growing market for pet products, including dog toys. However, little is known about the hazardous substances released from dog toys. This study aims to examine the potential presence of obesogens, a subset of endocrine-disrupting chemicals (EDCs) that are widely utilized as raw materials in the manufacture of dog toy components, and their effects on dog health. To achieve this, we adapted and employed a migration method typically used for children's products to simulate obesogen exposure in dogs through sucking or chewing toys. We demonstrated that out of various obesogens, bisphenol A (BPA) was released from dog toys into synthetic saliva, whereas phthalates and azo dyes were not detected in any of the leachates. Additionally, we found that BPA induced adipogenic differentiation in canine adipose-derived stem cells (cADSCs). Our RNA sequencing experiments revealed that BPA alters the adipogenesis-related gene signature in cADSCs by elevating the expression levels of ADIPOQ, PLIN1, PCK1, CIDEC, and FABP4. The associated transcriptional changes are involved in the peroxisome proliferator-activated receptor (PPAR) signaling pathway, which may contribute to the promotion of adipogenesis by BPA. Our findings suggest that companion dogs are at risk of BPA exposure, which may contribute to obesity in dogs. Therefore, the implementation of precautionary measures is crucial.

Optimizing the Adipogenic Induction Protocol Using Rosiglitazone Improves the Physiological Parameters and Differentiation Capacity of Adipose Tissue-Derived Mesenchymal Stem Cells for Horses, Sheep, Dogs, Murines, and Humans

The investigation of adipose tissue-derived mesenchymal stem cells (ASCs) has received considerable interest in regenerative medicine. A nontoxic adipogenic induction protocol valid for cells of different mammalian species has not been described. This study aims to establish an adipogenic differentiation protocol suitable for horses, sheep, dogs, murines, and human cells. An optimized rosiglitazone protocol, consisting of 5% fetal calf serum in Dulbecco's Modified Eagle's Medium, 10 μg/mL insulin, 0.55 μg/mL transferrin, 6.8 ng sodium selenite, 1 μM dexamethasone, and 1-5 μM of rosiglitazone, is compared to the 3-isobutyl-1-methylxantine (IBMX) protocol, where rosiglitazone was replaced with 0.5 mM IBMX and 0.2 mM indomethacin. Cell viability, cytotoxicity, a morphometric analysis of the lipid, and the expression of adipogenic markers for 14 days were assessed. The data revealed that using 5 µM of rosiglitazone promotes the adipogenic differentiation capacity in horse, sheep, and dog cells compared to IBMX induction. Meanwhile, marked reductions in the cell viability and cell number with the IBMX protocol were detected, and rosiglitazone increased the cell number and lipid droplet size, prevented apoptosis, and upregulated FABP-4 and Leptin expression in the cells of most of the species. Our data revealed that the rosiglitazone protocol improves the adipogenesis of ASCs, together with having less toxicity, and should be considered for cell reproducibility and clinical applications targeting obesity.

Feline umbilical cord-derived mesenchymal stem cells: isolation, identification, and antioxidative stress role through NF-κB signaling pathway

At present, the differentiation potential and antioxidant activity of feline umbilical cord-derived mesenchymal stem cells (UC-MSCs) have not been clearly studied. In this study, feline UC-MSCs were isolated by tissue adhesion method, identified by flow cytometry detection of cell surface markers (CD44, CD90, CD34, and CD45), and induced differentiation toward osteogenesis and adipogenesis in vitro. Furthermore, the oxidative stress model was established with hydrogen peroxide (H₂O₂) (100 μM, 300 μM, 500 μM, 700 μM, and 900 μM). The antioxidant properties of feline UC-MSCs and feline fibroblasts were compared by morphological observation, ROS detection, cell viability via CCK-8 assay, as well as oxidative and antioxidative parameters via ELISA. The mRNA expression of genes related to NF-κB pathway was detected via quantitative real-time polymerase chain reaction, while the levels of NF-κB signaling cascade-related proteins were determined via Western Blot. The results showed that feline UC-MSCs highly expressed CD44 and CD90, while negative for CD34 and CD45 expression. Feline UC-MSCs cultured under osteogenic and adipogenic conditions showed good differentiation capacity. After being exposed to different concentrations of H₂O₂ for eight hours, feline UC-MSCs exhibited the significantly higher survival rate than feline fibroblasts. A certain concentration of H₂O₂ could up-regulate the activities of SOD2 and GSH-Px in feline UC-MSCs. The expression levels of p50, MnSOD, and FHC mRNA in feline UC-MSCs stimulated by 300 μM and 500 μM H₂O₂ significantly increased compared with the control group. Furthermore, it was observed that 500 μM H₂O₂ significantly enhanced the protein levels of p-IκB, IκB, p-p50, p50, MnSOD, and FHC, which could be reversed by BAY 11-7,082, a NF-κB signaling pathway inhibitor. In conclusion, it was confirmed that feline UC-MSCs, with good osteogenesis and adipogenesis abilities, had better antioxidant property which might be related to NF-κB signaling pathway. This study lays a foundation for the further application of feline UC-MSCs in treating the various inflammatory and oxidative injury diseases of pets.

A simplified and defined serum-free medium for cultivating fat across species

Cultivated meat is a promising technology with the potential to mitigate the ethical and environmental issues associated with traditional meat. Fat plays a key role in the meat flavor; therefore, development of suitable adipogenic protocols for livestock is essential. The traditional adipogenic cocktail containing IBMX, dexamethasone, insulin and rosiglitazone is not food-compatible. Here, we demonstrate that of the four inducers only insulin and rosiglitazone are necessary in both serum-free (DMAD) and serum-containing media, with DMAD outperforming FBS. Two glucocorticoid receptor activators, progesterone and hydrocortisone, found in DMAD and FBS, affect differentiation homogeneity, without playing an essential role in activating adipogenic genes. Importantly, this protocol leads to mature adipocytes in 3D culture. This was demonstrated in both media types and in four species: ruminant and monogastric. We therefore propose a simplified one-step adipogenic protocol which, given the replacement of rosiglitazone by a food-compatible PPARγ agonist, is suitable for making cultivated fat.

Honeysuckle Berry (Lonicera caerulea L.) Inhibits Lipase Activity and Modulates the Gut Microbiota in High-Fat Diet-Fed Mice

Honeysuckle berry (HB, Lonicera caerulea L.) is an oriental herbal medicine reported to have beneficial effects on metabolic disorders, such as obesity and non-alcoholic fatty liver disease. The fruit part of HB is rich in anthocyanin, a type of polyphenol. Most studies credit the antioxidant and anti-inflammatory properties of HB as the mechanisms of its effectiveness. This study investigated the inhibitory effects of HB on lipase using an in vitro assay and the modulatory effect of HB on gut microbiota in high-fat diet (HFD)-fed mice. HB inhibited pancreatic lipase activity with IC50 values of approximately 0.47 mg/mL. The fecal triglyceride (TG) levels were higher from the HFD of the HB-fed mice than they were for the control mice. Moreover, the fecal microbiota from the HFD of the HB-fed mice had relatively lower Firmicutes and higher Bacteroidetes than that from the HFD-only mice. These results suggest that HB modulates gut microbiota composition, which may contribute to body fat reduction. Hence, HB could present a useful agent for treating metabolic diseases through lower TG uptake and the regulation of gut microflora.