Maternal zinc alleviates tert-butyl hydroperoxide-induced mitochondrial oxidative stress on embryonic development involving the activation of Nrf2/PGC-1α pathway.

BACKGROUND: Mitochondrial dysfunction induced by excessive mitochondrial reactive oxygen species (ROS) damages embryonic development and leads to growth arrest. OBJECTIVE: The purpose of this study is to elucidate whether maternal zinc (Zn) exert protective effect on oxidative stress targeting mitochondrial function using an avian model. RESULT: In ovo injected tert-butyl hydroperoxide (BHP) increases (P < 0.05) hepatic mitochondrial ROS, malondialdehyde (MDA) and 8-hydroxy-2-deoxyguanosine (8-OHdG), and decreases (P < 0.05) mitochondrial membrane potential (MMP), mitochondrial DNA (mtDNA) copy number and adenosine triphosphate (ATP) content, contributing to mitochondrial dysfunction. In vivo and in vitro studies revealed that Zn addition enhances (P < 0.05) ATP synthesis and metallothionein 4 (MT4) content and expression as well as alleviates (P < 0.05) the BHP-induced mitochondrial ROS generation, oxidative damage and dysfunction, exerting a protective effect on mitochondrial function by enhancing antioxidant capacity and upregulating the mRNA and protein expressions of Nrf2 and PGC-1α. CONCLUSIONS: The present study provides a new way to protect offspring against oxidative damage by maternal Zn supplementation through the process of targeting mitochondria involving the activation of Nrf2/PGC-1α signaling.

Effect of Maternal Marginal Zinc Deficiency on Development, Redox Status, and Gene Expression Related to Oxidation and Apoptosis in an Avian Embryo Model.

Maternal severe zinc (Zn) deficiency resulted in growth retardation and high mortality during embryonic development in human. Therefore, this study is aimed at evaluating the effect of maternal marginal Zn deficiency on the development and redox status to avoid severe Zn deficiency using an avian model. A total of 324 laying duck breeders at 214 days old were randomly allotted into 3 dietary Zn levels with 6 replicates of 18 ducks per replicate. The birds were fed experimental diets including 3 dietary supplemental Zn levels of 0 mg/kg (maternal Zn-deficient group, 29.2 mg Zn/kg diet), 60 mg/kg (maternal Zn-adequate group), and 120 mg/kg (maternal Zn-high group) for 6 weeks. Dietary Zn levels had on effect on egg production and fertility (P > 0.05), whereas dietary Zn deficiency decreased breeder plasma Zn concentration and erythrocytic alkaline phosphatase activity at week 6 and inhibited erythrocytic 5'-nucleotidase (5'-NT) activity at weeks 2, 4, and 6 (P < 0.05), indicating that marginal Zn-deficient status occurred after Zn depletion. Maternal marginal Zn deficiency increased embryonic mortality and contents of superoxide anion radical, MDA, and PPC and reduced MT content and CuZnSOD activity in duck embryonic livers on E29. The MDA content was positively correlated with embryonic mortality. Maternal marginal Zn deficiency increased BCL2-associated X protein and Caspase-9 mRNA expressions as well as decreased B-cell lymphoma-2 and MT1 mRNA and signal AKT1 and ERK1 protein expressions (P < 0.05). Breeder plasma Zn concentration and erythrocytic 5'-NT activities at week 6 were positively correlated with GSH-Px activity and GPx, MT1, and BCL2 mRNA expressions in embryonic livers on E29. In conclusion, erythrocytic 5'-NT activity could be more rapid and reliable to monitor marginal Zn-deficient status. Marginal Zn deficiency impaired hatchability and antioxidant defense system and then induced oxidative damage and apoptosis in the embryonic liver, contributing to the greater loss of duck embryonic death.

Effects of Selenium-Enriched Yeast on Performance, Egg Quality, Antioxidant Balance, and Egg Selenium Content in Laying Ducks.

This study investigated the effects of dietary selenium-enriched yeast (Se yeast) supplementation on the laying performance, egg quality, plasma antioxidant balance, and egg selenium (Se) content in laying Longyan ducks. A total of 480 32-week-old ducks were randomly divided into four dietary treatments, each consisting of six replicates of 20 ducks. The dietary treatments were a control basal diet and basal diets with supplementation of 0.05, 0.15, and 0.25 mg Se/kg via Se yeast. The analyzed Se contents of the four diets were 0.15, 0.21, 0.36, and 0.43 mg Se/kg, respectively. Dietary Se yeast supplementation had no apparent effects on laying performance and egg quality (p > 0.05), but it improved the antioxidant balance of ducks, as inferred by greater glutathione peroxidase and catalase activities, and decreased the malondialdehyde content in plasma of ducks (p < 0.05). It was suggested that the Se content in the basal diet containing 0.15 mg/kg of Se requirement is adequate for productive performance, but not for the antioxidant balance of laying ducks. Besides that, the Se contents in the yolk, albumen, and whole egg increased linearly as the Se supplementation levels increased. With more feeding days, the Se contents in the yolk and whole egg from non-Se-yeast-supplemented ducks increased linearly (p < 0.05), while those from Se-yeast-supplemented ducks showed a quadratic relationship (p < 0.05). In conclusion, the Se content of the basal diet at 0.15 mg/kg was adequate for laying performance and egg quality traits in laying ducks. Dietary Se yeast supplementation is beneficial to improve the antioxidant balance of laying ducks and increase the Se deposition in eggs for producing Se-enriched eggs. Based on the quadratic model or the quadratic broken-line model analyses, supplemental 0.19 mg Se/kg via Se yeast, with a total equivalent of 0.34 mg Se/kg in the diet, could provide the optimum antioxidant balance in laying ducks. Dietary supplementation of 0.25 mg Se/kg via Se yeast, with a total equivalent of 0.40 mg Se/kg in the diet, could lead to achieving the desired Se content in the whole egg.

[Effects of needle knife relaxing therapy on tension of local soft tissue and pain of osteoarthritis of knee].

OBJECTIVE: To probe into the mechanism and methods of needle knife relaxing therapy for treatment of osteoarthritis of knee from biomechanical view. METHODS: Needle knife relaxing therapy was given to 92 pain points around the knee joint in 14 cases of osteoarthritis of knee, and the displacement of the local pain point under the stress of 500 g (L500 g) was measured and the VAS scores were recorded before and after treatment. RESULTS: L500 g of the pain point was (4.72+/-1.03) mm before treatment and (5.39+/-1.01) mm after treatment with a very significant difference before and after treatment (P<0.01), and VAS score was (7.10+/-1.49) points before treatment and (1.49+/-1.24) points after treatment with a very significant difference before and after treatment (P<0.01), and there was a linear correlation between the changes of L500 g and VAS scores. CONCLUSION: There was close connection between the local pain and tension of local soft tissue in knee osteoarthritis. The needle knife relaxing therapy can relieve the neurovascular compression or traction syndrome by relaxing the local contracted, adhesive soft tissue, so as to relieve tension pain and finally recover internal force equilibrium of the knee joint.

[Evaluation on clinical therapeutic effect of needle-knife therapy on cervical spondylosis].

OBJECTIVE: To compare therapeutic effects of needle-knife therapy and acupuncture on cervical spondylosis. METHODS: Multi-central clinical randomized controlled trial was adopted. The patients were divided into a needle-knife treatment group treated with needle-knife therapy at the upper and lower interspinal ligaments of the affected vertebral body and bilateral posterior joint capsules; and the acupuncture control group were treated with acupuncture at Laozhen, Ashi points and cervical Jiaji points, etc. The short-term and the long-term therapeutic effects were observed at the end of the therapeutic course and 6 months after the end of the therapeutic course. RESULTS: The short-term therapeutic effect and the long-term therapeutic effect were 91.3% and 94.7% in the needle-knife treatment group and 59.4% and 56.6% in the acupuncture control group, respectively, with a very significant difference between the two groups (P < 0.01). CONCLUSION: The needle-knife treatment in the therapeutic effect on cervical spondylosis is superior to acupuncture treatment.