Tavener Selena K, Jackson Matthew I, Panickar Kiran S
Science and Technology Center, Hill's Pet Nutrition, Inc., Topeka, KS, United States.
Curr Dev Nutr. 2024 Feb 28;8(4):102128. doi: 10.1016/j.cdnut.2024.102128. eCollection 2024 Apr.
Ketogenic foods limit digestible carbohydrates but contain high fat, and have antioxidant and anti-inflammatory effects as well as improving mitochondrial function. β-Hydroxybutyrate (BHB), 1 of the ketone bodies, reduces the proinflammatory NLR family pyrin domain containing 3 inflammasomes, as well as chemokines in cultures.
We assessed the immune-modulating effects of 2 low-carbohydrate (LoCHO) foods varying in protein and fat and compared their effects with a food replete with high-carbohydrate (HiCHO) in healthy canines.
Dogs were fed control food [HiCHO; ketogenic ratio (KR: 0.46) followed by LoCHO_PROT (KR: 0.97), then LoCHO_FAT (KR: 1.63) or LoCHO_FAT followed by LoCHO_PROT. Each food was fed for 5 wk, with collections in the 5th wk; 15 wk feeding total. Gene expression for circulating inflammatory cytokines from 10 dogs was assessed using the Canine RT Profiler polymerase chain reaction array, and fold changes were calculated using the ΔΔCt method.
LoCHO_FAT significantly increased circulating β-hydroxybutyrate compared with both HiCHO and LoCHO_PROT. When compared with HiCHO, there was a significant decrease in several proinflammatory cytokines/chemokines in LoCHO_PROT and LoCHO_FAT groups, including chemokine (C-C motif) ligand (CCL)1, CCL8, CCL13, CCL17, CCL24, chemokine (C-X3-C motif) ligand 1, chemokine (C-X-C motif) receptor 1, Interleukin-10 receptor alpha ((IL)-10RA), IL-1 receptor antagonist, IL-5, and secreted phosphoprotein 1 (all < 0.05). Interestingly, a subset of inflammatory proteins that decreased in LoCHO_PROT but not in LoCHO_FAT included IL-33, IL-6 receptor, IL-7, IL-8, Nicotinamide phosphoribosyltransferase, and tumor necrosis factor (TNF) receptor superfamily member 11B. In contrast, the decrease in inflammatory markers in LoCHO_FAT, but not in LoCHO_PROT, included complement component 5, granulocyte colony-stimulating factor or G-CSF, interferon-γ, IL-3, IL-10RB, IL-17C, Tumor necrosis factor superfamily (TNFSF)13, TNFSF13B, and TNFSF14. Decreased concentrations of selected cytokines indicate that both low-carbohydrate foods exert an anti-inflammatory effect and provide a strong rationale for testing their efficacy in dogs with inflammatory conditions.
Both LoCHO_PROT and LoCHO_FAT foods might be important as part of immune-modulating therapeutic nutritional strategies to reduce inflammation to maintain health in canines. Our study identifies several inflammatory genes that are reduced when fed ketogenic food that were not previously reported.
生酮食物限制可消化碳水化合物，但含有高脂肪，具有抗氧化和抗炎作用，还能改善线粒体功能。β-羟基丁酸（BHB）是酮体之一，可减少培养物中促炎的含NLR家族pyrin结构域的3型炎性小体以及趋化因子。
我们评估了两种蛋白质和脂肪含量不同的低碳水化合物（LoCHO）食物的免疫调节作用，并将它们的效果与富含高碳水化合物（HiCHO）的食物在健康犬中的效果进行比较。
给犬喂食对照食物[HiCHO；生酮比例（KR：0.46），随后是LoCHO_PROT（KR：0.97），然后是LoCHO_FAT（KR：1.63）或LoCHO_FAT，随后是LoCHO_PROT。每种食物喂食5周，在第5周进行采集；总共喂食15周。使用犬类RT Profiler聚合酶链反应阵列评估10只犬循环炎性细胞因子的基因表达，并使用ΔΔCt方法计算倍数变化。
与HiCHO和LoCHO_PROT相比，LoCHO_FAT显著增加了循环β-羟基丁酸水平。与HiCHO相比，LoCHO_PROT组和LoCHO_FAT组中几种促炎细胞因子/趋化因子显著降低，包括趋化因子（C-C基序）配体（CCL）1、CCL8、CCL13、CCL17、CCL24、趋化因子（C-X3-C基序）配体1、趋化因子（C-X-C基序）受体1、白细胞介素-10受体α（（IL）-10RA）、IL-1受体拮抗剂、IL-5和分泌性磷蛋白1（均<0.05）。有趣的是，在LoCHO_PROT中减少但在LoCHO_FAT中未减少的炎性蛋白子集包括IL-33、IL-6受体、IL-7、IL-8、烟酰胺磷酸核糖基转移酶和肿瘤坏死因子（TNF）受体超家族成员11B。相反，在LoCHO_FAT中而非LoCHO_PROT中减少的炎性标志物包括补体成分5、粒细胞集落刺激因子或G-CSF、干扰素-γ、IL-3、IL-10RB、IL-17C、肿瘤坏死因子超家族（TNFSF）13、TNFSF13B和TNFSF14。所选细胞因子浓度的降低表明两种低碳水化合物食物均发挥抗炎作用，并为测试它们在患有炎症性疾病的犬中的疗效提供了有力依据。
LoCHO_PROT和LoCHO_FAT食物作为免疫调节治疗性营养策略的一部分，对于减轻炎症以维持犬类健康可能都很重要。我们的研究鉴定出了几种喂食生酮食物时会减少的炎性基因，这些基因以前未被报道过。
