Anticarcinogenic activity of methanol extract of Melastoma malabathricum leaves is attributed to the presence of phenolics compounds and the activation of endogenous antioxidant system

Melastoma malabathricum (M. malabathricum) extracts have been reported to exert various pharmacological activities including antioxidants, anti-inflammatory and antiproliferative activities. The objective of the present study was to determine the anticarcinogenic activity of its methanol extract (MEMM) against the azoxymethane (AOM)-induced early colon carcinogenesis in rats. Rats were randomly assigned to five groups (n=6) namely normal control, negative control, and treatment (50, 250 or 500 mg/kg of MEMM) groups. Colon tissues were harvested for histopathological analysis and endogenous antioxidant system determination. MEMM was also subjected to HPLC analysis. Findings showed that MEMM significantly (p<0.05) reversed the AOM-induced carcinogenicity by: i) reducing the formation of aberrant crypt foci (ACF) in colon tissues, and; ii) enhancing the endogenous antioxidant activity (catalase, superoxide dismutase and glutathione peroxidase). Moreover, various phenolics has been identified in MEMM. In conclusion, MEMM exerts the in vivo anticarcinogenic activity via the activation of endogenous antioxidant system and synergistic action of phenolics.

Melatonin Promotes SGT1-Involved Signals to Ameliorate Drought Stress Adaption in Rice

Drought has become one of the environmental threats to agriculture and food security. Applications of melatonin (MT) serve as an effective way to alleviate drought stress, but the underlying mechanism remains poorly understood. Here, we found that foliar spray of 100-µM MT greatly mitigated the severe drought stress-induced damages in rice seedlings, including improved survival rates, enhanced antioxidant system, and adjusted osmotic balance. However, mutation of the suppressor of the G2 allele of skp1 (OsSGT1) and ABSCISIC ACID INSENSITIVE 5 (OsABI5) abolished the effects of MT. Furthermore, the upregulated expression of OsABI5 was detected in wild type (WT) under drought stress, irrespective of MT treatment, whereas OsABI5 was significantly downregulated in sgt1 and sgt1abi5 mutants. In contrast, no change of the OsSGT1 expression level was detected in abi5. Moreover, mutation of OsSGT1 and OsABI5 significantly suppressed the expression of genes associated with the antioxidant system. These results suggested that the functions of OsSGT1 in the MT-mediated alleviation of drought stress were associated with the ABI5-mediated signals. Collectively, we demonstrated that OsSGT1 was involved in the drought response of rice and that melatonin promoted SGT1-involved signals to ameliorate drought stress adaption.

In pursuit of incorporation of markers of oxidative stress in traditional biochemical panels in clinical Chemistry: A risk assessment step in diagnosis and biotherapy

Chemical pathology (clinical chemistry/biochemistry) is the branch of laboratory medicine concerned with the detection of alterations in the chemical constituents and biochemical mechanisms, which ensure health, culminating in disease. The disease itself is a pattern of response to some insult or injury resulting in a disturbed function or structure. It is often difficult to ascertain precisely the point of transition from health to a disease state. Pathological changes, including metabolic and molecular perturbations, with the potential to progress to clinical disease, are also present in healthy populations, noteworthy are the reactive oxygen species such as hydroxyl radicals with the propensity to cause oxidative DNA damage. Biochemical profiles or panels such as liver function tests, renal function tests, bone profile, lipid profile, acid-base, and critical care have served as biomarkers employed in indicating the presence of or measuring the progress of the disease, as well as the effect of treatment. Oxidative stress, an imbalance between bio-available antioxidants and reactive species, is now widely recognized as accompanying most pathological states. Hence, the exclusion of antioxidant components in biochemical profiles appears a grave oversight. Basic components of the antioxidant system, glutathione (GSH), zinc, uric acid, ascorbic acid, and α-tocopherol, may be selected for incorporation. GSH is particularly important; as a scavenger for damaging oxidative intermediates in cells, it promises to be a good predictor of disease progression and prognosis. Including the antioxidant component into traditional profiles may aid physicians in more confidently ruling out disease, enabling further investigations, and/or reassuring patients. It is proposed that redefining the traditional profiles in chemical pathology by incorporating the indexes of the antioxidant system promises considerable improvement in the risk assessment process, in disease detection and recognition of the threshold of clinical concern in disease management and biotherapy.

Role of Nrf2 in Pancreatic Cancer

Pancreatic tumors are a serious health problem with a 7% mortality rate worldwide. Inflammatory processes and oxidative stress play important roles in the development of pancreatic diseases/cancer. To maintain homeostasis, a balance between free radicals and the antioxidant system is essential. Nuclear Factor Erythroid 2-Related Factor 2/NFE2L2 (Nrf2) and its negative regulator Kelch-Like ECH-Associated Protein 1 (Keap1) provide substantial protection against damage induced by oxidative stress, and a growing body of evidence points to the canonical and noncanonical Nrf2 signaling pathway as a pharmacological target in the treatment of pancreatic diseases. In this review, we present updated evidence on the activation of the Nrf2 signaling pathway and its importance in pancreatic cancer. Our review covers potential modulators of canonical and noncanonical pathway modulation mechanisms that may have a positive effect on the therapeutic response. Finally, we describe some interesting recent discoveries of novel treatments related to the antioxidant system for pancreatic cancer, including natural or synthetic compounds with therapeutic properties.