Pyruvate kinase plays a pivotal role in regulating cell metabolism. The final and rate-limiting step of glycolysis is the conversion of Phosphoenolpyruvate (PEP) to Pyruvate, which is catalyzed by Pyruvate Kinase. There are four isomeric, tissue-specific forms of Pyruvate Kinase found in mammals: PKL, PKR, PKM1, and PKM2. PKM1 and PKM2 are formed bya single mRNA transcript of the PKM gene by alternative splicing. The oligomers of PKM2 exist in high activity tetramer and low activity dimer forms. The dimer PKM2 regulates the rate-limiting step of glycolysis that shifts the glucose metabolism from the normal respiratory chain to lactate production in tumor cells. Besides its role as a metabolic regulator, it also acts as protein kinase, which contributes to tumorigenesis. This review is focused on the metabolic role of pyruvate kinase M2 in normal cells vs. cancerous cells and its regulation at the transcriptional level. The review also highlights the role of PKM2 as a potential diagnostic marker and as a therapeutic target in cancer treatment.

Background/Objectives. The aim of this study was to evaluate oxidant and antioxidant status in children with different grades of Protein Energy Malnutrition (PEM).Subjects/Methods. A total of two hundred fifty (250) children (age range: 6 months to 5 years) living in eastern UP, India, were recruited. One hundred and ninety-three (193) of these children had different grades of PEM (sixty-five (65) children belong to mild, sixty (60) to moderate, and sixty-eight (68) to severe group). Grading in group was done after standardization in weight and height measurements. Fifty-seven (57) children who are age and and sex matched, healthy, and well-nourished were recruited from the local community and used as controls after checking their protein status (clinical nutritional status) with height and weight standardization. Redox homeostasis was assessed using spectrophotometric/colorimetric methods.Results. In our study, erythrocyte glutathione (GSH), plasma Cu, Zn-superoxide dismutase (Cu,Zn-SOD,EC 1.15.1.1), ceruloplasmin (Cp), and ascorbic acid were significantly (P<0.001) more decreased in children with malnutrition than controls. Plasma malondialdehyde (MDA), and protein carbonyl (PC) were significantly (P<0.001) raised in cases as compared to controls.Conclusion. Stress is created as a result of PEM which is responsible for the overproduction of reactive oxygen species (ROSs). These ROSs will lead to membrane oxidation and thus an increase in lipid peroxidation byproducts such as MDA and protein oxidation byproducts such as PC mainly. Decrease in level of antioxidants suggests an increased defense against oxidant damage. Changes in oxidant and antioxidant levels may be responsible for grading in PEM.

Cervical cancer is the second most common cause of cancer-related death among women worldwide, especially in developing countries. Oxidative stress has been associated with cervical cancer. Many studies demonstrated that the low level of antioxidants induces the production of free radicals that cause lipid peroxidation, DNA, and protein damage leading to mutations that favors malignant transformation. This is a case-control institutional study conducted to evaluate the level of oxidative stress in cervical cancer patients and the age-matched healthy controls. We measured level of TBARS expressed as MDA, activity of SOD and GSH level by the spectrophotometric method, and level of 8-OHdG was estimated using a competitive sandwich ELISA assay. Our results showed a significant increase in the level of lipid peroxidation in group IV when compared to the control, group II and group III (p < 0.001). The activity of SOD was also significantly higher in group IV when compared to the control group (p < 0.001), group II (p < 0.001), and group III (p < 0.001). The level of GSH was also significantly lower in group IV when compared to the control group (p < 0.01), group II (p < 0.01), and group III (p < 0.01). The level of 8-OHdG was significantly higher in group IV than in the other groups (p < 0.01). The results suggest that oxidative stress is involved in the pathogenesis of cervical cancer, which is demonstrated by an increased level of lipid peroxidation and higher levels of 8-OHdG and an altered antioxidant defense system.

Background: Several studies using animal models have shown that oxidative stress during pregnancy may play an important role in causing birth defects. Congenital anomalies affect an estimated 270,000 newborns who die during the first 28 days of life every year from different birth defects. Hence, at present many research works are going on to reduce the infant mortality from congenital anomaly. ^[1] Objective: The objective was to measure the oxidant and antioxidant level in the serum of newborn babies with the congenital anomaly and compare these levels with age and sex matched normal neonates. This is to identify any role of oxidative stress in the causation of congenital anomaly. Materials and Methods: This case-control study included 159 participants: 106 newborns with the congenital anomaly and 53 healthy newborns. The markers of oxidative stress like serum malondialdehyde (MDA) level, protein carbonyl (PC) level, and the activity of antioxidants such as Vitamin C, glutathione were measured in both cases (neonates with congenital anomaly) and controls (normal healthy neonates). These parameters were statistically compared. Results: MDA levels and PC levels were significantly higher (P < 0.0001), and Vitamin C and reduced glutathione levels were significantly lower (P < 0.0001), in newborns with congenital malformation than in healthy newborns. Conclusions: Increased lipid peroxidation and protein carbonylation might play an important role in the pathogenesis of congenital anomaly. Impairment of the free radical/antioxidant balance is leading to increased free radical damage in neonates with congenital malformation.