Possible protective effect of zinc administration on renal and cognitive changes occurring in uninephrectomized adult male Wistar rats.

NEW FINDINGS: What is the central question of this study? Are renal changes occurring post-nephrectomy accompanied by cognitive changes, and does early administration of zinc supplements such as ZnSO4 to uninephrectomized rats ameliorate the renal and cognitive changes if present? What is the main finding and its importance? Uninephrectomy-induced renal changes were accompanied by species-atypical behaviour in rats in both Morris water maze and T maze tests, together with hypozincaemia and hippocampal inflammatory and oxidative changes. Early zinc administration to uninephrectomized rats ameliorated the renal, behavioural, hippocampal and serum zinc changes. ABSTRACT: Cognitive impairment is increasingly recognized as an important consequence of kidney disease in humans. Kidney donation is a safe procedure but is known to increase the long-term risk of cardiovascular and kidney disease. Whether kidney donation impairs cognitive function is not known. In the present study, we examined whether the renal changes occurring post-nephrectomy were accompanied by cognitive changes as well, and whether early administration of zinc supplements such as ZnSO4 to uninephrectomized (UNX) rats could ameliorate the renal and cognitive changes if present. The present study included 30 adult male Wistar rats that were randomly assigned to three groups (n = 10 per group): sham-operated rats, UNX and UNX treated with ZnSO4 for 20 weeks. Before termination, rats were subjected to 24-h urine collection and behavioural testing with the Morris water maze and T maze tests. UNX induced significant proteinuria, renal functional, fibrotic and oxidative changes, as well as increased renal desmin expression. UNX rats also showed significant behavioural changes indicating spatial learning and memory affection, together with decreased hippocampal brain derived neurotrophic factor (BDNF) and antioxidant capacity, and increased glial fibrillary acidic protein (GFAP), nitric oxide and malondialdehyde. In addition, UNX induced significant hyperglycaemia and dyslipidaemia, as well as significant reduction in serum zinc, copper and selenium. Early administration of ZnSO4 starting 1 week post-nephrectomy significantly ameliorated renal and behavioural changes, as well as hippocampal oxidative, BDNF and GFAP changes. Additionally, Zn recovered serum changes of triglycerides, cholesterol, zinc and copper. Therefore, early administration of zinc to humans undergoing nephrectomy may be of benefit and should be considered in human trials.

Coenzyme Q10 alleviates testicular endocrine and spermatogenic dysfunction induced by high-fat diet in male Wistar rats: Role of adipokines, oxidative stress and MAPK/ERK/JNK pathway.

The current study investigated the possible protective effects of Coenzyme Q10 (Co Q10 ) on rat model of high-fat diet (HFD) induced testicular dysfunction. Thirty male Wistar rats were allocated randomly into three groups: control, HFD, HFD + Co Q10 (75 mg/kg/day) groups. Animals were sacrificed after 3 months and epididymal sperm suspension, blood, and testes were collected for further analysis. In comparison to the untreated HFD group, the Co Q10 treated group revealed significantly increased serum testosterone, adiponectin levels, and decreased LH, FSH, and leptin levels. In addition, HFD resulted in significant increase in testicular oxidative stress (increased MDA, iNOS, NO, XO & decreased catalase, SOD, GSH) and inflammation (increased pJNK/JNK, pERK/ERK, and p-p38MAPK/MAPK), while Co Q10 was effective to ameliorate these changes. In addition, Co Q10 significantly increased sperm count, motility and viability that were markedly deteriorated by HFD. Regarding testicular ultrastructure, seminiferous tubular diameter and epithelium height were reduced in HFD group and Co Q10 significantly improved these testicular changes. Finally, a significant reduction in spermatogenic cell proliferation was detected by PCNA fluorescent expression and Co Q10 significantly reversed this change. In summary, our results indicated that Co Q10 could suppress testicular dysfunction produced by HFD. This protective effect could be attributed to its antioxidant, anti-inflammatory properties and to its effect on adipokines and spermatogenic cell proliferation. So, Co Q10 may be a promising food supplement to protect against testicular dysfunction induced by HFD.

Amino acid changes during transition to a vegan diet supplemented with fish in healthy humans.

PURPOSE: To explore whether changes in dietary protein sources can lower plasma branched-chain amino acids (BCAAs), aromatic amino acids and sulfur amino acids (SAAs) that are often elevated in the obese, insulin-resistant state and in type 2 diabetes. METHODS: Thirty-six subjects (mean age 31 ± 2 years) underwent a voluntary abstinence from meat, poultry, eggs, and dairy products for 6 weeks, while enriching the diet with fish, in fulfillment of a religious fast. Subjects were assessed 1 week before the fast (V1), 1 week after initiation of the fast (V2) and in the last week of the fast (V3). Thirty-four subjects completed all three visits. RESULTS: Fasting plasma BCAAs decreased at V2 and remained low at V3 (P < 0.001 for all). Valine showed the greatest decline, by 20 and 19 % at V2 and V3, respectively. Phenylalanine and tryptophan, but not tyrosine, also decreased at V2 and V3. The two proteinogenic SAAs, methionine and cysteine, remained stable, but the cysteine product, taurine, decreased from 92 ± 7 µmol/L to 66 ± 6 (V2; P = 0.003) and 65 ± 6 µmol/L (V3; P = 0.003). A progressive decline in plasma glutamic acid, coupled with an increase in glutamine, was observed. Plasma total and LDL cholesterol decreased at V2 and V3 (P < 0.001 for all). CONCLUSION: Changing dietary protein sources to plant- and fish-based sources in an ad libitum setting lowers the plasma BCAAs that have been linked to diabetes risk. These findings point to habitual diet as a potentially modifiable determinant of fasting plasma BCAA concentrations.