bims-vitmet 2025-04-27 papers

Issue of 2025–04–27
two papers selected by
Onurkan Karabulut, Berkeley City College

BMC Genomics. 2025 Apr 24. 26(1): 397

Vitamin A mediates FABP4 to regulate intramuscular fat production: a new target and strategy for optimizing beef quality.

Yaping Song, Jiupan Zhang, Chao Jiang, Xiaoyu Song, Xiaodong Chen, Sayed Haidar Abbas Raza, Sameer Dinkar Pant, Yun Ma, Linsen Zan, Dawei Wei, Guijie Zhang.

Beef quality is critically determined by intramuscular fat (IMF) deposition. Retinoic acid (RA), the active metabolite of vitamin A, plays an essential regulatory role in IMF development. To systematically investigate RA-mediated regulation of IMF formation in cattle, we established a concentration gradient of RA supplementation and employed a systematic screening approach to identify the optimal dosage for modulating bovine intramuscular adipocytes (IMAs) proliferation and differentiation. Subsequently, leveraging integrated multi-omics approaches, we screened the key downstream molecular targets through which RA governs IMF biosynthesis, and clarified the potential regulatory mechanism of this target. Our experimental data establish that RA promotes the proliferation of IMAs through modulation of G1/S phase progression. Concurrently, RA enhances triglyceride biosynthesis in IMAs by activating PPARγ-mediated cell differentiation and LPL-mediated intracellular lipid accumulation. Integrated transcriptomics and metabonomics analyses identified FABP4, CD36, EBF2, LRP1 and CAV1 as key candidate genes involved in RA-mediated IMF production. Functional interrogation revealed that FABP4 knockdown markedly attenuated lipid accumulation in IMAs, a phenotype rescued through RA supplementation, confirming FABP4 as the critical effector mediating vitamin A's regulation of bovine IMF deposition. These results provide a new understanding of how nutritional factors affect beef quality at the molecular level.

Keywords: Bovine; FABP4; Intramuscular fat; Vitamin A

DOI: https://doi.org/10.1186/s12864-025-11544-7

BMJ Case Rep. 2025 Apr 22. pii: e265159. [Epub ahead of print]18(4):

Rare co-occurrence of severe vitamin A deficiency in an early adolescent girl with Bartter syndrome.

Muhammad Sikandar Tahir, Muhammad Imran Riazat, Dean Huggard, Mehdi Abbas.

We report a rare case of an early adolescent girl with Bartter syndrome presenting with severe vitamin A deficiency, characterised by decreased visual acuity, xerophthalmia and corneal ulceration. The deficiency appears to have resulted from poor nutritional intake due to a restricted diet, unhealthy dietary choices compounded by gastrointestinal discomfort and the challenges posed by Bartter syndrome.The patient, diagnosed in her early infancy with Bartter syndrome, exhibited features typical of this inherited renal tubular disorder, including electrolyte imbalance, polyuria and failure to thrive. Her long-standing gastrointestinal discomfort, likely related to high-dose non-steroidal anti-inflammatory drugs (indomethacin) and oral potassium supplements, further compromised her nutritional intake.She was managed with high-dose vitamin A supplementation, resulting in partial visual recovery. This case underscores the importance of monitoring fat-soluble vitamin levels in Bartter syndrome patients, who are at risk for malabsorption and dietary deficiencies. We suggest that routine screening for Vitamin A deficiency in patients with Barter syndrome may be beneficial, though this recommendation is derived from our observation from this case rather than established evidence.

Keywords: Childhood nutrition (paediatrics); Ophthalmology; Renal medicine

DOI: https://doi.org/10.1136/bcr-2025-265159