The precise functions and molecular mechanisms of microRNAs (miRNAs) in adipocytes are primarily unknown. Studies have demonstrated that miR-193b plays a pivotal role in the differentiation of preadipocytes. Herein, we evaluated the effects of bta-miR-193b on the growth and development of adipocytes, using the EdU cell proliferation method, flow cytometry analysis, CCK-8 assay, RT-qPCR, Western blotting, and oil red O staining. We observed that the overexpression of bta-miR-193b significantly affected the differentiation, proliferation, and apoptosis of adipocytes. The results of the dual-fluorescent reporter vector experiments demonstrated that bta-miR-193b directly targeted Acyl-CoA synthetase short-chain family member 2 (ACSS2). Additionally, the effects of ACSS2 overexpression on the proliferation and apoptosis in adipose cells were the opposite of those induced by bta-miR-193b. We also demonstrated that ACSS2 can significantly promote the expression of AKT and pAKT proteins. Therefore, this study presents a novel mechanism by which bta-miR-193b regulates adipocyte development by targeting ACSS2.

In livestock production, oxidative stress (OS) is ubiquitous, reducing animal productivity and product quality. Hence, investigating the mechanisms of oxidative stress in livestock and inhibiting oxidative stress-induced damage is crucial. Curcumin, a plant-derived bioactive compound, exhibits antioxidant and anti-apoptotic properties. Adipose-derived stem cells (ADSCs) from animal adipose tissue are easily accessible and possess multilineage differentiation potential. Therefore, this work utilized bovine ADSCs to establish an oxidative stress model and investigated the effects of curcumin on oxidative stress and apoptosis. Firstly, bovine ADSCs were isolated and cultured from fetal calf subcutaneous adipose tissue. Their surface markers were identified by immunofluorescence, confirming the expression of CD29, CD44, CD73, CD90, CD105 and Vimentin, but not CD34, indicative of mesenchymal stem/progenitor cell characteristics. Secondly, to explore the effects of curcumin on oxidative damage and apoptosis in bovine ADSCs, an oxidative stress model was induced using H2O2. CCK-8 assays showed significantly reduced cell viability and SOD activity, along with increased malondialdehyde (MDA) and reactive oxygen species (ROS) levels, indicating successful modeling. RT-qPCR further confirmed that 500 μM of H2O2 treatment for 24 h promoted apoptosis. Herein, CCK-8 assays indicated a significant reduction in cell viability at >8 μM of curcumin. Thirdly, using 4 μM and 8 μM of curcumin for pre-protection, 8 μM maintained SOD activity, reduced MDA and ROS, inhibited apoptosis-related gene changes (Bcl-2, Bax, Caspase-3), and suppressed apoptosis according to a TUNEL assay. Fourthly, curcumin’s autophagy-inducing potential was hypothesized, which was confirmed by increased LC3-II and decreased P62 expression upon co-treatment with 3-MA. 3-MA inhibited curcumin’s antioxidant and anti-apoptotic effects, suggesting that curcumin’s antioxidant and anti-apoptotic roles may involve autophagy induction. In conclusion, bovine ADSCs are abundant, easily accessible, and multipotent, making them suitable for in vitro expansion. Curcumin alleviated H2O2-induced oxidative stress in bovine ADSCs, with curcumin also inhibiting apoptosis, likely through autophagy induction. This study validates the protective role of curcumin in bovine ADSCs, with potential applications in livestock production.

As an important part of the circadian rhythm, the circadian regulation factor 2 of cryptochrome (CRY2), regulates many physiological functions. Previous studies have reported that CRY2 is involved in growth and development. However, the relationship between CRY2 gene polymorphism and cattle carcass traits remains unclear. The aim of this study was to detect the possible variations of the CRY2 gene and elucidate the association between the CRY2 gene and carcass traits in the Shandong Black Cattle Genetic Resource (SDBCGR) population (n = 705). We identified a 24-bp deletion variation (CRY2-P6) and a 6-bp insertion variation (CRY2-P7) in the bovine CRY2 gene. The frequency of the homozygous II genotype is higher than the heterozygous ID genotype in both two loci. In addition, CRY2-P6 was consistent with HWE (p > 0.05). Importantly, the CRY2-P6 variant was significantly associated with 12 carcass traits, including gross weight, ribeye, high rib, thick flank, etc. and the II was the dominant genotype. The CRY2-P7 site was also significantly correlated with five traits (gross weight, beef-tongue, etc.). Collectively, these outcomes indicated that the two Indel loci in the CRY2 gene could be used for marker-assisted selection of cattle carcass traits.

Ferroptosis has been increasingly implicated in adipose and muscle dysfunction, systemic metabolic disturbances, and several diseases in livestock, which necessitates effective and side-effect-free inhibition strategies. Phloretin, a dihydrochalcone with excellent antioxidant and anti-inflammatory properties, may have the potential to restrain cell ferroptosis. Herein, phloretin was verified to significantly inhibit (1S,3R)-RSL3-induced ferroptosis by reducing intracellular MDA, Fe ² ⁺, and ROS levels and restoring cell total antioxidant capacity in bovine and mouse preadipocytes or myoblasts. It also alleviated oxidative stress (OS), a vital inducer of ferroptosis, by restoring antioxidant enzyme activity in the above cells and obese mice. In vivo, phloretin gavage significantly reversed the trend where high-fat diet (HFD)-induced OS promoted the expression of ferroptosis-promoting genes and proteins (e.g., ACSL4 and PTGS2) while inhibiting the expression of ferroptosis-negative regulators (e.g., Fth1 and Gpx4 ). Unlike most flavonoids that exert anti-inflammatory or antioxidant activities by altering the gut microbiota composition, metagenomic sequencing analysis of cecal contents from phloretin-gavaged and HFD mice revealed that phloretin exerts its antioxidative and ferroptosis-inhibitory effects independent of modulating gut microbiota diversity. Further transcriptomic analyses of mouse adipose tissues revealed that phloretin alleviated ferroptosis in adipocytes by modulating the transcription of genes enriched in AMPK and PPAR signaling pathways, such as Camkk2 . Hence, based on multi-omics analysis combined with in vivo and in vitro verification, phloretin effectively alleviated the OS to further inhibit ferroptosis of adipose or muscle cells through the AMPK-PPAR pathway, which can provide new research ideas for ameliorating adipose or myocyte dysfunction induced by ferroptosis in animals. Graphical Abstract

The beef cattle industry has seen rapid expansion, necessitating the optimization of slaughter traits for enhanced economic benefits. Copy number variation (CNV) has emerged as a pivotal molecular marker in marker-assisted selection (MAS) for genetic improvement in livestock. In this study, we focused on CNVs within the HIF1A and HIF2A genes, which play crucial roles in hypoxic signaling and energy metabolism. Four CNVs were identified in the bovine HIF1A gene and three in HIF2A using the AAOD database. In Gaoqing Black cattle (GQB), the distribution of CNVs for both genes was investigated, revealing predominantly median copy numbers. Association analysis showed a significant relation between CNVs in HIF1A and carcass traits such as cervical vertebrae (CNV1), initial weight and beef diaphragm (CNV2), slaughter weight and chuck (CNV3), and femur and chuck (CNV4) (p < 0.05 or p < 0.01). Similarly, CNVs in HIF2A are associated with traits like beef diaphragm, beef knuckle bone, and beef tendon (CNV1), longissimus dorsi width and beef diaphragm (CNV2), and slaughter weight and limb weights (CNV3) (p < 0.05 or p < 0.01). These findings provide insights into the potential influence of CNVs in HIF1A and HIF2A on carcass traits in Gaoqing Black cattle, offering a theoretical basis for genetic improvement in beef cattle breeding.