Sistematični pregled vloge vitamina C pri sladkorni bolezni tipa 2

Horvat, Nuša (author), Mravljak, Janez (mentor)

Sladkorna bolezen je skupina presnovnih bolezni, za katere je značilna dolgotrajna hiperglikemija zaradi nezadostne proizvodnje inzulina ali neustreznega celičnega odgovora na proizveden inzulin. Med ključnimi dejavniki v patofiziologiji sladkorne bolezni tipa 2 in njenih zapletih so oksidativne spremembe. Reaktivne kisikove spojine prispevajo k inzulinski rezistenci, poškodujejo beta celice trebušne slinavke in povzročajo kronično vnetje. Nastanek, napredovanje bolezni ter njeni zapleti so tesno povezani s povečano tvorbo radikalov in zmanjšano antioksidativno obrambo. Iz tega razloga so številne študije raziskovale vpliv jemanja vitamina C, kot enega najmočnejših antioksidantov, za izboljšanje nadzora glikemije in zmanjšanja inzulinske rezistence. Sistematično smo pregledali vse dostopne randomizirane raziskave, ki so raziskovale vlogo vitamina C pri uravnavanju sladkorne bolezni tipa 2. Na podlagi rezultatov, pridobljenih iz raziskav, smo želeli ugotoviti, ali dodajanje vitamina C vpliva na inzulinsko rezistenco, raven glukoze in vrednosti glikiranega hemoglobina v krvi. Z ustreznim iskalnim nizom smo v podatkovnih bazah PubMed, Web of Science in Google učenjaku našli skupno 757 raziskav, od katerih smo jih 19 vključili v naš sistematičen pregled. Ovrednotili smo kakovost izbranih raziskav in za vsako izpisali osnovne podatke s kratkim povzetkom, jih nato analizirali in med seboj primerjali. Rezultati so pokazali, da ima uživanje vitamina C potencial za izboljšanje glikemičnega stanja in inzulinske občutljivosti pri bolnikih s sladkorno boleznijo tipa 2, ker znatno zniža ravni glukoze v krvi, glikiranega hemoglobina ter inzulina na tešče. Izboljšanje se je še posebej kazalo pri odmerkih vitamina C večjih ali enakih 1000 mg, trajanju terapije vsaj 12 tednov ter ob sočasnem jemanju antidiabetikov. Rezultati vključenih raziskav ter naše ugotovitve odpirajo možnosti za vključitev vitamina C kot dodatne terapije pri obvladovanju sladkorne bolezni tipa 2, inzulinske odpornosti ter s tem k boljši kakovosti življenja bolnikov s sladkorno boleznijo tipa 2. Kljub obetavnim rezultatom pa je na tem področju treba izvesti dodatne raziskave visoke kakovosti, da bi naše ugotovitve potrdile.

• Language: Slovenian
• Keywords: Sladkorna bolezen tipa 2, vitamin C, antioksidant, sistematičen pregled
• Work type: Master's thesis/paper
• Organization: FFA - Faculty of Pharmacy
• Year: 2024
• PID: 20.500.12556/RUL-163166
• Publication date in RUL: 03.10.2024

Secondary language

• Language: English
• Title: Systematic review of the vitamin C role in type 2 diabetes

Abstract

Diabetes mellitus is a group of metabolic diseases characterised by prolonged hyperglycaemia due to insufficient insulin production or an inadequate cellular response to the insulin produced. Oxidative changes are among the key factors in the pathophysiology of type 2 diabetes and its complications. Reactive oxygen species contribute to insulin resistance, cause damage to pancreatic beta-cells and lead to chronic inflammation. The development, progression and complications of the disease are closely related to increased radical production and reduced antioxidant defences. For this reason, many studies have investigated the impact of taking vitamin C, as one of the most potent antioxidants, to improve glycemic control and reduce insulin resistance. We systematically reviewed all available randomised trials that investigated the role of vitamin C in the management of type 2 diabetes. Based on the results obtained from the studies, we wanted to determine whether vitamin C supplementation affects insulin resistance, blood glucose levels and glycated haemoglobin levels. A search of PubMed, Web of Science and Google Scholar databases found a total of 757 studies, 19 of which were included in our systematic review. We evaluated the quality of the selected studies, extracted the basic data for each study with a short summary, then analysed and compared them with each other. The results showed that vitamin C supplementation has the potential to improve glycaemic control and insulin sensitivity in patients with type 2 diabetes by significantly lowering blood glucose, glycated haemoglobin and fasting insulin levels. Improvement was particularly evident with doses of vitamin C greater than or equal to 1000 mg, with a duration of therapy of at least 12 weeks and with concomitant antidiabetic treatment. The results of the included studies and our findings raise the possibility of including vitamin C as an adjunctive therapy in the management of type 2 diabetes, insulin resistance, and thus in improving the quality of life of patients with type 2 diabetes. However, despite the promising results, further high quality research in this area is needed to confirm our findings.

• Keywords: Type 2 diabetes, vitamin C, antioxidant, systematic review