Enhancement of beta-catenin in cardiomyocytes suppresses survival protein expression but promotes apoptosis and fibrosis

Background: Beta-catenin has been implicated in cell-cell communication in a wide variety of developmental and physiological processes. Defective Wnt signaling could result in various cardiac and vascular abnormalities. Little is known regarding Wnt/frizzled pathway in cardiomyocyte apoptosis. Methods: In this study, the role of b-catenin in apoptosis was investigated in H9c2 cardiomyocytes and primary cardiomyocytes isolated in diabetic Wistar rats. The cardiomyocytes were transfected with porcine cytomegalovirus (pCMV)-b-catenin plasmid in order to overexpress b-catenin. Results: The transcription factor displayed a significant nuclear localization in Wistar rats with cardiac hypertension. Transfection of b-catenin plasmid induced apoptosis and reduced expression of survival pathway markers in cardiomyocytes in a dose-dependent manner. Furthermore, expression of fibrosis protein markers was upregulated by the overexpression. Conclusions: Taken together, these results revealed that altered Wnt/b-catenin signaling might provoke heart failure. (Cardiol J 2017; 24, 2: 195–205

Bioactive Peptide Improves Diet-Induced Hepatic Fat Deposition and Hepatocyte Proinflammatory Response in SAMP8 Ageing Mice

Background/Aims: High-fat diet (HFD)-induced nonalcoholic fatty liver disease (NAFLD) poses therapeutic challenges in elderly subjects. Due to lack of efficient drug therapy, plant-based bioactive peptides have been studied as alternative strategy in NAFLD and for less toxicity in elderly. To mimic fatty liver in aging conditions, researchers highly commended the genetically engineered strains SAMP8 (senescence-accelerated mice prone 8). However, there is a paucity of reports about the anti-steatosis effects of bioactive peptides against fatty liver development under a combined action of high-fat diet exposure and aging process. This study was conducted to evaluate the activity of DIKTNKPVIF peptide synthesized from alcalase-generated potato protein hydrolysate (PH), on reducing HFD-driven and steatosis-associated proinflammatory reaction in ageing model. Methods: Five groups of six-month-old SAMP8 mice (n=4, each) were fed either a normal chow (NC group) for 14 weeks upon sacrifice, or induced with a 6-week HFD feeding, then treated without (HCO group) or with an 8-week simultaneous administration of peptide (HPEP group), protein (HPH group) or probucol (HRX group). Liver organs were harvested from each group for histological analysis and immunoblot assay. Results: In contrast to NC, extensive fat accumulation was visualized in the liver slides of HCO. Following the trends of orally administered PH, intraperitoneally injected peptide reduces hepatic fat deposition and causes at protein level, a significant decrease in HFD-induced proinflammatory mediators p-p38 MAPK, FGF-2, TNF-α, IL-6 with concomitant reactivation of AMPK. However, p-Foxo1 and PPAR-α levels were slightly changed. Conclusion: Oral supplementation of PH and intraperitoneal injection of derived bioactive peptide alleviate proinflammatory reaction associated with hepatosteatosis development in elderly subjects, through activation of AMPK

Novel mutations in ATPase 8, ND1 and ND5 genes associated with peripheral neuropathy of diabetes

Type 2 Diabetes (T2D), being a complex, multi factorial metabolic disorder, its chronic complications development remains puzzled. In this case report, we describe four novel mutations in Cyt b, ATPase 8, ND1 and ND5 genes’ synergistic activity as plausible factors for the secondary complications of a patient with chronic T2D

Neferine, a bisbenzylisoquinoline alkaloid, offers protection against cobalt chloride-mediated hypoxia-induced oxidative stress in muscle cells

Background: Neferine, a bisbenzylisoquinoline alkaloid, isolated from Nelumbo nucifera has a wide range of biological activities. Cobalt chloride (CoCl2) was known to mimic hypoxic condition. In the present study, we assessed the cytoprotective effect of neferine against CoCl2-induced oxidative stress in muscle cells. Methods: Rhabdomyosarcoma cells were exposed to different concentrations of CoCl2, and the IC50 value was determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Lactate dehydrogenase and NO assays were performed in order to determine the cytotoxic effect of CoCl2. Reactive oxygen species generation and cellular antioxidant status were determined for evaluating oxidative stress. For analyzing the effect of neferine on CoCl2-induced apoptosis, propidium iodide staining was performed. Results: The results of the present study indicate that CoCl2 induces cell death in a dose-dependent manner. Neferine pretreatment at 700 nM concentration offers better cytoprotection in the cells exposed to CoCl2. Lactate dehydrogenase and NO release in the culture medium were restored after neferine pretreatment. CoCl2 triggers time-dependent reactive oxygen species generation in muscle cells. Further, results of propidium iodide staining, mitochondrial membrane potential, and intracellular calcium accumulation confirm that neferine offers protection against CoCl2-induced hypoxic injury. Depleted activities of antioxidants such as superoxide dismutase, catalase, glutathione peroxidase, and glutathione S-transferase due to CoCl2 exposure were also reinstated in the group that received neferine pretreatment. Conclusion: Our study suggests that neferine from N. nucifera offers protection to muscle cells by counteracting the oxidative stress induced by CoCl2

Tinospora cordifolia extract prevents cadmium-induced oxidative stress and hepatotoxicity in experimental rats

Background: Cadmium (Cd) pollution is of serious concern due to its toxic effects in both humans and animals. The study investigates the protective effect of Tinospora cordifolia stem methanolic extract (TCME) on Cd induced hepatotoxicity. Objective(s): The objective of the study was to explore the hepatoprotective effects of T. cordifolia extract. Materials and methods: Rats were administered orally with Cd (5 mg/kg) and TCME (100 mg/kg) for 28 days. At the end of the treatment period, serum and liver tissues homogenates were subjected to biochemical analysis. Results: Cd treated rats showed increased activities of the serum marker enzymes of liver damage such as AST and ALT along with increased levels of LPO and protein carbonyl content in liver tissues. Cd treatment also leads to decreased activities of endogenous antioxidants (SOD, CAT, GSH, GPx and GST), membrane ATPases (Na+K+ATPase, Ca2+ATPase and Mg2+K+ATPase) and the tissue glycoprotein levels (hexose, fucose, hexosamine and sialic acid). Histological analysis revealed vacuolar degeneration of hepatocytes with focal necrosis upon Cd administration. TCME co-treatment restored the biochemical and histological alterations caused by Cd intoxication to near normal levels. Conclusion: The results of the present investigation reveal the hepatoprotective nature of T. cordifolia against Cd induced hepatotoxicity. Keywords: Cadmium, Oxidative stress, Tinospora cordifolia, Hepatotoxicity, Antioxidan

Modulatory effect of Tinospora cordifolia extract on Cd-induced oxidative stress in Wistar rats

Background: Cadmium (Cd), a nonessential heavy metal, is a major environmental and public health concern. Oxidative stress plays an important role in Cd-induced kidney dysfunction. Tinospora cordifolia, a medicinal plant rich in phytochemicals, possesses antioxidant activity. The objective of the present study was to assess the protective effect of Tinospora cordifolia-stem methanolic extract (TCE) on Cd-induced nephrotoxicity in Wistar rats. Methods: Male Wistar rats were administered ∼5 mg/kg body weight Cd orally and 100 mg/kg body weight TCE for 28 days. At the end of Cd and TCE treatment, biochemical assays were performed in serum and tissue homogenate. Results: Cd-induced oxidative stress in the kidney resulted in increased levels of lipid peroxidation and protein carbonyl content with a significant decrease in cellular antioxidants, such as reduced GSH, SOD, CAT, GPX, and GST. Cd-induced nephrotoxicity was further confirmed by marked changes in the histology of the kidney and increased levels of kidney markers. Additionally, Cd-treated rats showed alterations in membrane-bound ATPase activity and decreased levels of tissue glycoproteins. Cotreatment with TCE considerably reduced the biochemical alterations in serum and renal tissue induced by Cd, and also restored ATPase activity and glycoproteins to near normal levels. Conclusion: Our results suggested that TCE with its antioxidant effect offered cytoprotection against Cd-induced toxicity in kidneys by restoring the altered cellular antioxidants and renal markers. TCE treatment for 28 days reversed ATPase activity and tissue glycoprotein levels. These results revealed the protective effect of TCE on Cd-induced toxicity in kidneys and oxidative stress

Reversal of doxorubicin resistance in lung cancer cells by neferine is explained by nuclear factor erythroid-derived 2-like 2 mediated lung resistance protein down regulation

Aim: Development of multi drug resistance and dose limiting cardiotoxicity are hindering the use of Doxorubicin (Dox) in clinical settings. Augmented dox efflux induced by lung resistance protein (LRP) over expression has been related to multi drug resistance phenotype in various cancers. An alkaloid from lotus, Neferine (Nef) shows both anticancer and cardioprotective effects. Here, we have investigated the interconnection between nuclear factor erythroid-derived 2-like 2 (NRF2) and LRP in Dox resistance and how Nef can overcome Dox resistance in lung cancer cells by altering this signaling.Methods: Anti-proliferative and apoptotic-inducing effects of Nef and Dox combination in Parental and Dox resistant lung cancer cells were determined in monolayers and 3D spheroids. Intracellular Dox was analyzed using flow cytometry, siRNA knockdown and western blot analysis were used to elucidate NRF2-LRP crosstalk mechanism.Results: We observed that the Dox resistant lung cancer cells expressed higher levels of LRP, reduced glutathione (GSH) and NRF2. Combination of Dox and Nef induced apoptosis, leads to reactive oxygen species (ROS) generation, GSH depletion and reduction in LRP levels contributing to higher intracellular and intranuclear Dox accumulation. The use of N-acetylcysteine and knockdown studies confirmed an important role of ROS and NRF2 in LRP down regulation. Presence of NRF2 binding sites in LRP is support of direct interaction between LRP and NRF2.Conclusion: Nef sensitizes lung cancer cells to Dox by increasing intracellular and/or intra nuclear Dox accumulation via LRP down regulation. This is mediated by redox regulating NRF2. This decoded crosstalk mechanism reinforces the role of NRF2 and LRP in Dox resistance and as an important anticancer target