ArticleFoods (Basel, Switzerland)2026
Effect of Vitamin K Supplementation on Testosterone Production in a Rat Model of Late-Onset Hypogonadism.
Article in Foods (Basel, Switzerland), 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
1 citing paper in PubMed.
- Vitamin K as an Endocrine Modulator: Mechanistic Links to Glucose Metabolism and Beyond.Nutrients · 2026Review
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Authors and funding
17 authors.
Funding
Abstract
Late-onset hypogonadism (LOH) is an age-related condition characterized by a decline in testosterone (Ts) levels and associated symptoms that impair quality of life in older men. Although Ts replacement therapy is available, its clinical use is limited by adverse effects. Vitamin K (VK) is a fat-soluble vitamin that functions as a cofactor for γ-glutamylcarboxylase and plays important roles in blood coagulation and bone homeostasis. Menaquinone-4 (MK-4), a VK homolog predominantly found in animal-derived foods, has been shown to enhance Ts production in healthy male rats. However, whether this effect occurs under low-Ts conditions remains unclear. In this study, we investigated the effects of VK on LOH using a leuprorelin acetate (LA)-induced low-Ts rat model. Male Sprague-Dawley rats were administered sustained-release LA and fed a control diet or diets supplemented with VK1 or MK-4 (75 mg/kg) for 4 weeks. Compared with the control group, MK-4 supplementation significantly ameliorated the reduction in serum Ts levels and seminiferous tubule diameter, whereas VK1 supplementation showed no significant effects. Furthermore, MK-4 supplementation activated the protein kinase A signaling pathway, which is directly involved in testicular Ts production. These findings suggest that MK-4 supplementation may represent a novel nutritional strategy for the management of LOH.
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