Park Sunmin, Kang Suna, Kim Da Sol, Zhang Ting
Department of Food & Nutrition, Obesity/Diabetes Center, Hoseo University, Asan 31499, Korea.
Department of Bioconvergence, Hoseo University, Asan 31499, Korea.
Life (Basel). 2022 Jan 26;12(2):177. doi: 10.3390/life12020177.
A testosterone deficiency potentially increases osteoarthritis (OA) symptoms, and dietary protein and exercise affect them. However, their efficacy and their interactions are still unclear. We hypothesized that a high-protein diet (HPD) and regular exercise modulated OA symptoms in testosterone-deficient rats, and it was examined in bilateral orchidectomized (ORX) and monoiodoacetate (MIA)-injected rats. The ORX rats were given a 30 energy percent (En%) protein (HPD) or 17.5 En% protein (CD). Both groups had 39 En% fat in the diet. Non-ORX-CD rats (sham-operation of ORX) were given the CD and no exercise (normal control). After an eight-week intervention, all rats had an injection of MIA into the left knee, and the treatments were continued for an additional four weeks. The non-ORX-CD rats showed a significant increase in body weight compared to the ORX rats, but the ORX rats had elevated fat mass. ORX exacerbated the glucose tolerance by lowering the serum insulin concentrations and increasing insulin resistance. ORX exacerbated the OA symptoms more than the non-ORX-CD. The HPD and exercise improved bone mineral density and glucose metabolism without changing serum testosterone concentrations, while only exercise increased the lean body mass and decreased fat mass, lipid peroxide, and inflammation. Exercise, but not HPD, reduced the OA symptoms, the weight distribution in the left leg, and running velocity and provided better relief than the non-ORX-CD rats. Exercise with HPD improved the histology of the knee joint in the left leg. Exercise reduced lipid peroxide contents and TNF-α and IL-1β mRNA expression in the articular cartilage, while exercise with HPD decreased MMP-3 and MMP-13 mRNA expression as much as in the non-ORX-CD group. In conclusion, moderate aerobic exercise with HPD alleviated OA symptoms and articular cartilage degradation in a similar way in the non-ORX rats with OA by alleviating inflammation and oxidative stress.
睾酮缺乏可能会加重骨关节炎（OA）症状，而膳食蛋白质和运动对其有影响。然而，它们的功效及其相互作用仍不明确。我们假设高蛋白饮食（HPD）和规律运动可调节睾酮缺乏大鼠的OA症状，并在双侧睾丸切除（ORX）和注射单碘乙酸盐（MIA）的大鼠中进行了研究。给ORX大鼠喂食能量占比30%（En%）的蛋白质（HPD）或能量占比17.5%的蛋白质（对照饮食，CD）。两组饮食中脂肪含量均为39%En。非ORX-CD大鼠（ORX的假手术组）给予CD且不运动（正常对照）。经过八周干预后，所有大鼠左膝注射MIA，并继续治疗四周。与ORX大鼠相比，非ORX-CD大鼠体重显著增加，但ORX大鼠脂肪量升高。ORX通过降低血清胰岛素浓度和增加胰岛素抵抗而加重葡萄糖耐量。与非ORX-CD大鼠相比，ORX更易加重OA症状。HPD和运动可改善骨矿物质密度和葡萄糖代谢，而血清睾酮浓度无变化，仅运动可增加瘦体重、减少脂肪量、脂质过氧化物和炎症。运动而非HPD可减轻OA症状、左腿重量分布、跑步速度，并比非ORX-CD大鼠提供更好的缓解效果。HPD联合运动可改善左腿膝关节组织学。运动可降低关节软骨中脂质过氧化物含量以及TNF-α和IL-1β mRNA表达，而HPD联合运动可使MMP-3和MMP-13 mRNA表达降低程度与非ORX-CD组相同。总之，在患有OA的非ORX大鼠中，适度有氧运动联合HPD通过减轻炎症和氧化应激，以类似方式减轻了OA症状和关节软骨降解。
