Methotrexate (MTX) is recognized as an anti-metabolite in cancer chemotherapy and is associated with various toxicities assigned to inflammation and oxidative stress. Rutin has been reported to have significant anti-inflammatory, antioxidant along with antiulcer properties. The present study was undertaken to corroborate the effect of rutin against MTX induced intestinal toxicity in experimental animals. Six groups of rats (n = 6) were dosed with normal saline (3 ml/kg,i.p.); MTX (2.5 mg/kg,i.p.); rutin (50 and 100 mg/kg,i.p.); rutin + MTX (50 mg/kg + 2.5 mg/kg,i.p.); rutin + MTX (100 mg/kg + 2.5 mg/kg,i.p.) for seven consecutive days and sacrificed on eighth day. The intestinal contents were scrutinized physiologically (pH, total acidity, free acidity, CMDI), biochemically (TBARS, protein carbonyl, SOD, catalase and GSH) and for immunoregulatory cytokines (IL-2, IL-4 and IL-10). The administration of rutin demonstrated significant protection against intestinal lesions damaged by MTX. The treatment with rutin elicited noticeable inhibition of free acidity (26.20 %), total acidity (22.05 %) and CMDI (1.16 %) in the experimental animals similar to control. In MTX treated toxic group, the levels of oxidative markers and immunoregulatory cytokines significantly increased in comparison to control, which was subsequently restored after rutin treatment. Rutin also demonstrated 75.63, 81.00 and 80.43 % inhibition of cyclooxygenase-1 and 2, and 15-lipoxygenase respectively. The positive modulation of MTX toxicity could be attributed to the free radical scavenging and anti-inflammatory (dual inhibition of arachidonic acid pathways) potential of rutin.
It is well known that solid hypoxic tumour cells oxidise glucose through glycolysis, and the end product of this pathway is fermented into lactate which accumulates in the tumour microenvironment (TME). Initially, it was proclaimed that cancer cells cannot use lactate; therefore, they dump it into the TME and subsequently augment the acidity of the tumour milieu. Furthermore, the TME acts as a lactate sink with stope variable amount of lactate in different pathophysiological condition. Regardless of the amount of lactate pumped out within TME, it disappears immediately which still remains an unresolved puzzle. Recent findings have paved pathway in exploring the main role of lactate acidosis in TME. Cancer cells utilise lactate in the de novo fatty acid synthesis pathway to initiate angiogenesis and invasiveness, and lactate also plays a crucial role in the suppression of immunity. Furthermore, lactate re-programme the lipid biosynthetic pathway to develop a metabolic symbiosis in normoxic, moderately hypoxic and severely hypoxic cancer cells. For instance: severely hypoxic cancer cells enable to synthesizing poly unsaturated fatty acids (PUFA) in oxygen scarcity secretes excess of lactate in TME. Lactate from TME is taken up by the normoxic cancer cells whereas it is converted back to PUFAs after a sequence of reactions and then liberated in the TME to be utilized in the severely hypoxic cancer cells. Although much is known about the role of lactate in these biological processes, the exact molecular pathways that are involved remain unclear. This review attempts to understand the molecular pathways exploited by lactate to initiate angiogenesis, invasiveness, suppression of immunity and cause re-programming of lipid synthesis. This review will help the researchers to develop proper understanding of lactate associated bimodal regulations of TME.
Particular dramatic macromolecule proteins are responsible for various cellular events in our body system. Lipids have recently recognized a lot more attention of scientists for understanding the relationship between lipid and cellular function and human health However, a biological membrane is formed with a lipid bilayer, which is called a P–L–P design. Our body system is balanced through various communicative signaling pathways derived from biological membrane proteins and lipids. In the case of any fatal disease such as cancer, the biological membrane compositions are altered. To repair the biological membrane composition and prevent cancer, dietary fatty acids, such as omega-3 polyunsaturated fatty acids, are essential in human health but are not directly synthesized in our body system. In this review, we will discuss the alteration of the biological membrane composition in breast cancer. We will highlight the role of dietary fatty acids in altering cellular composition in the P–L–P bilayer. We will also address the importance of omega-3 polyunsaturated fatty acids to regulate the membrane fluidity of cancer cells.
1 March 2018 in Prostaglandins & Other Lipid Mediators
Hypoxia‐inducible factor‐1alpha (HIF‐1α) is a major transcription factor that adapts to low oxygen homeostasis and regulates the expression of several hypoxic genes, which aid in cancer survival and development. It has recently piqued the interest of translational researchers in the disciplines of cancer sciences. Hypoxia triggers an ample adaptive mechanism mediated via the HIF‐1α transcriptional domain. Anaerobic glycolysis, angiogenesis, metastasis, and mitophagy are adaptive mechanisms that support tumor survival by promoting oxygen supply and regulating oxygen demand in hypoxic tumor cells. Throughout this pathway, the factor‐inhibiting HIF‐1α is a negative regulator of HIF‐1α leading to its hydroxylation at the C‐TAD domain of HIF‐1α under normoxia. Thus, hydroxylated HIF‐1α is unable to proceed with the transcriptional events due to interference in binding of C‐TAD and CBP/p300. From this review, we can hypothesize that remodeling of FIH‐1 activity is a unique mechanism that decreases the transcriptional activity of HIF‐1α and, as a result, all of its hypoxic consequences. Hence, this review manuscript details the depth of knowledge of FIH‐1 on hypoxia‐associated cellular and molecular events, a potential strategy for targeting hypoxia‐induced malignancies.