Phototherapy motivates protein and lipid oxidation in jaundiced term and late term neonates

Background: Hyperbilirubinemia is one of the most important complications encountered in neonatal units. It has been proposed that phototherapy yields oxidative stress. Therefore, this study was undertaken to survey the levels of antioxidant and oxidative stress in the serum of neonates before and after phototherapy. Methods: This study was performed on thirty-five healthy, late preterm (>35 weeks) and term newborns aged 6-10 days, who underwent phototherapy due to hyperbilirubinemia (>14.00 mg/dL). Infants with a congenital malformation, birth asphyxia, sepsis, signs and symptoms suggestive of severe illness, and receiving phototherapy before recruitment to the study were excluded. Blood samples were taken to determine total serum bilirubin, total antioxidant capacity (TAC) of serum, malondialdehyde (MDA), advanced oxidation protein products (AOPP) as markers of the intensity of oxidative stress and inflammation with photometric methods, reduced and oxidized glutathione (GSH) by HPLC-UV as well as the ratio of them before and after phototherapy. Results: TAC, GSH and bilirubin levels were significantly lower after phototherapy than before it, but reversely about levels of MDA, AOPP and oxidized GSH in addition to the ratio of reduced to oxidized GSH (p<0.05-0.001). AOPP and MDA showed a high negative correlation with bilirubin (respectively R=-0.985 and -0.986, p<0.001)) while vice versa about TAC and GSH (R=0.975 and 0.988, P<0.001). Conclusion: Phototherapy induces oxidative stress and inflammation not only due to the elevation of protein and lipid oxidation but also with reducing of antioxidant markers of serum

Effect of Cysteine on Transforming Growth Factor β1 as the Main Cause of Renal Disorder in a Rat Model of Diabetic Nephropathy

​Background and purpose: Glycation products, oxidative stress, and inflammation contribute to the development of diabetic nephropathy (DN) due to the elevation of transforming growth factor-β1 (TGF-β1). This study aimed at investigating the effect of Cysteine (Cys) on TGF-β in DN rat model. Materials and methods: In this experimental study, 40 male Wistar rats were randomly divided into four groups (n=10 per group): control, Cys, DN, and DN + Cys. DN was induced in rats by nephrectomy of the left kidney and injection of streptozotocin. The Cys and DN groups were treated with Cys (0.05% in dirking water) for three months. Glucose, insulin, diverse glycation products, lipid profile, oxidative stress markers, TNF-α, proteinuria, and serum creatinine levels were determined in all rats. Data analysis was done in SPSS V16. Results: Cys decreased the sera level of TGF-β1, renal dysfunction parameters, diverse Glycation, oxidative stress, and inflammatory markers in DN rats. Furthermore, the treatment improved glycemia and dyslipidemia (P> 0.001). Conclusion: Cysteine with antioxidant, anti-glycating, and anti-inflammatory properties ameliorated DN owing to advantageous effects on glucose and lipid metabolism in rats with diabetic nephropathy. Furthermore, this treatment showed multiple protective effects on kidney by reducing the TGF- β1 levels