L-theanine is the unique amino acid found in tea plants, has antioxidant and antiinflammatory activities, and functions in mental concentration and sleep quality. In this study, it is aimed to investigate the effects of L-theanine on doxorubicin (DOX, a chemotherapeutic agent) induced nephrotoxicity in rats, especially via GSH related enzymes. 32 male Sprague Dawley rats weighing 300-400 g were randomly assigned into 4 groups (n = 8) and the substances were given intraperitoneally to them: Control group (saline for 5 days); Theanine group (200 mg/kg/day theanine for 5 days); DOX group (single dose of 20 mg/kg DOX); DOX + Theanine group (20 mg/kg DOX at first day and 200 mg/kg/day theanine for 5 days). Kidney tissues were evaluated by histopathological analysis. Serum levels of blood urea nitrogen (BUN) and creatinine by spectrophotometrically; percentage of apoptosis indexes (AI%) in the tissues by TUNEL method; caspase-3 levels, reduced and oxidized glutathione (GSH and GSSG), gamma-glutamyltransferase 1 (GGT1), glutathione reductase (GR), glutathione peroxidase (GPx), and glutathione S-transferase (GST), nuclear factor kappa B p65 (NF-kB p65) by commercial kits; malondialdehyde (MDA) by spectrophotometrically were determined in plasma and kidney tissues. According to DOX group, the DOX + Theanine group has much lower tissue and plasma GSSG, GGT1, NF-κB p65 levels and tissue AI%, whereas significantly higher GSH levels and GPx, GR, GST activities (P < 0.05). It is suggested that L-theanine may have protective effects by enhancing effects on the antioxidant system of GSH and GSH-related enzymes against DOX-induced nephrotoxicity in rats. But this finding needs to be supported with further studies.

Aims: Polyphenolic chemicals, such as quercetin and curcumin have anti-cancer properties due to their antioxidant and anti-inflammatory properties. Quercetin and curcumin aids in detoxification by boosting enzyme function and eliminating free radicals. We aimed to conduct a detailed meta-analysis of research articles reporting the protective effects of curcumin and quercetin in cancer studies. Methods: The study was selected all studies over time carried out to date within the framework of our concept ,using various medical subject headings and databases like Elsevier, National Library of Frontiers, ResearchGate, Scopus Medicine, and Google Scholar. PRISMA guidelines was performed. The data management system played a significant role in locating and evaluating relevant articles, ensuring the accuracy and precision of the findings. Results: From a total of 85 articles accessed in this analysis, 4 studies on quercetin and 3 studies on curcumin were included. The analyzed studies show that quercetin and curcumin have anti-cancer benefits through various cellular pathways. Quercetin inhibits Twist in breast cancer cells, while curcumin reduces Akt/mTOR cellular signaling, enhances Bax expression, and triggers cell death. It also prevents cell growth in human lung cancer cells and bladder cancer. Curcumin control reactive oxygen species levels, inhibit cancer cell proliferation, and stimulate apoptotic pathways. They also influence cancer development by altering cellular signaling pathways and affecting non-coding RNAs. Conclusion: Our meta-analysis reports that quercetin and curcumin have the potential to be used in the treatment and prevention of cancer, it may be useful to investigate their synergistic effects.

Amaç: Paraoksonaz-1 (PON1) HDL yapısında bulunan, HDL ve LDL’yi oksidasyondan koruyarak aterosklerotik lezyonlardaki oksidatif stresi azaltan antioksidan bir enzimdir. Bu çalışmanın amacı, sağlıklı kişilerin oral trigliserid tolerans testine (OTTT) verdikleri cevaba göre PON1 enziminin paraoksonaz, arilesteraz ve laktonaz aktivitelerini değerlendirmektir. Gereç ve Yöntem: Gönüllüler, yaşları 18-55 arasında değişen 45 kadın ve 51 erkek olmak üzere toplam 96 sağlıklı bireyden oluşmaktadır. Gönüllüler, açlık ve OTTT sonrası 2, 4 ve 6’ncı saatlerdeki TG seviyeleri kullanılarak hesaplanan eğri altındaki alan (AUC) değerlerine göre üç farklı gruba ayrılmıştır. PON1 enzim aktiviteleri ve diğer parametreler OTTT cevabı düşük olan grup ile yüksek olan grup arasında karşılaştırıldı. PON1 enzim aktiviteleri spektrofotometrik metodlarla belirlendi. Bulgular: Erkeklerde üst grup ile alt grup karşılaştırıldığında aterojenik lipid profili, artmış total kolesterol ve LDL-K ile azalmış HDL-K düzeyleri gözlemlendi. PON1 laktonaz aktivitesi erkeklerde kadınlara göre anlamlı düşük bulundu (P<0.05). PON1 laktonaz aktivitesi her iki cinste de OTTT süresince zamana bağlı olarak artış gösterdi. Kadınlarda, üst grupta PON1 arilesteraz aktivitesi alt gruba göre anlamlı yüksek bulundu (P<0.022). Sonuç: OTTT cevabı yüksek olan üst grupların aterojenik lipit profiline sahip oldukları gözlemlenmiştir. PON1 enzim aktivitelerinin oksidatif strese bir cevap olarak postprandial dönemde genellikle artış eğiliminde olduğu, ayrıntılı çalışmalara ihtiyaç duyulduğu düşünülmüştür.

Aim; Publications investigating the potential of various nutritional supplements such as antioxidants, probiotics, and phytochemicals to improve drug-induced nephrotoxicity has increased both qualitatively and quantitatively over the years. This bibliometric analysis evaluated highly cited 100 articles on the protective effects of nutritional supplements against nephrotoxicity published between 2010 and 2023. Method; Articles published in these 13 years were evaluated through structured search in Scopus and Web of Science databases. Statistics and visualization techniques were done with VOSviewer and RStudio software. Results; The increase rate of articles published on this subject was found to be %450. The average h-index of selected studies was calculated as 60. A total of 534 authors and a citation rate of 86.95 were determined. The total citation mean was determined as 9 per year. The top 3 supplements were curcumin (n=7) melatonin and probiotics (n=5) in the trends. Cisplatin and gentamicin are used as toxic agents in 34% of the top 100 articles we researched, and they continue to be a trend. Conclusion; Trending and effective supplements in this field are curcumin, melatonin, berberine, quercetin and probiotics. Based on our investigations, we think that, the synergistic between the effective bioactive ingredients with probiotics and/or other functional foods suggest future novel approaches based on interactions involving microbiota, oxidative and inflammatory stress.