Basidiomycetes-X, an edible mushroom, alleviates the development of atopic dermatitis in NC/Nga mouse model.

Basidiomycetes-X (BDM-X) is a novel edible mushroom recently identified as a new fungi species and is effective against oxidative stress and anti-inflammation associated with immune response. However the effect of BDM-X on atopic dermatitis (AD) has not been elucidated. In this study, we have investigated the effect of BDM-X on AD skin lesions in NC/Nga mouse model. AD-like lesion was induced by the application of house dust mite extract (DfE) to the dorsal skin of NC/Nga mouse. After AD induction, BDM-X was administered once daily for 2 weeks. We have analyzed the effects of BDM-X on dermatitis severity, histopathological changes and changes in inflammatory and proinflammatory proteins expressions in DfE induced AD mice skin. Treatment with BDM-X attenuated the development of AD-like clinical symptoms and effectively inhibited hyperkeratosis, parakeratosis, acanthosis and mast cells in AD mice skin. Furthermore, BDM-X treatment inhibited DfE induced tumor necrosis factor (TNF)α, high mobility group protein (HMG)B1, nuclear factor kappa (NFκ)B and inflammatory cytokines. These results indicate that BDM-X inhibits AD through modulating Th1 and Th2 responses and diminishing the mast cells infiltration in the skin lesions in NC/Nga mice.

Curcumin alleviates renal dysfunction and suppresses inflammation by shifting from M1 to M2 macrophage polarization in daunorubicin induced nephrotoxicity in rats.

The molecular mechanism of curcumin in macrophage polarization remains unknown in renal failure. We examined, whether curcumin treatment is associated with the modulation of renal function and macrophage phenotype switch in daunorubicin (DNR) induced nephrotoxicity model. Sprague-Dawley rats were treated with a cumulative dose of 9mg/kg DNR (i.v). Followed by curcumin (100mg/kg) administration orally every day for 6weeks. DNR treated rats showed nephrotoxicity as evidenced by worsening renal function, which was assessed by measuring creatinine and blood urea nitrogen in serum. These changes were reversed by treatment with curcumin, which resulted in significant improvement in renal function. Furthermore, curcumin increased cluster of differentiation (CD)163 expression, and down-regulated renal expression of antigen II type I receptor (AT1R), endothelin (ET)1, ET receptor type A and B (ETAR and ETBR), CD68 and CD80. Renal protein expression of extracellular signal-regulated kinase (ERK)1/2 and nuclear factor (NF)κB p65 were increased in DNR treated rats, and treatment with curcumin attenuated these increased expression. Curcumin mediated a further increase in the levels of interleukin (IL)-10. In addition, the expression of M1 phenotype was increased in DNR treated rats, which were attenuated by curcumin. Taken together, our results demonstrated that polyphenol curcumin has an ability to improve renal function and might induce the phenotypic switching from M1 to M2 macrophage polarization in DNR induced nephrotoxicity in rats.

Telmisartan treatment targets inflammatory cytokines to suppress the pathogenesis of acute colitis induced by dextran sulphate sodium.

The renin angiotensin system (RAS) is essential for the regulation of cardiovascular and renal functions to maintain the fluid and electrolyte homeostasis. Recent studies have demonstrated a locally expressed RAS in various tissues of mammals, which is having pathophysiological roles in those organ system. Interestingly, local RAS has important role during the inflammatory bowel disease pathogenesis. Further to delineate its role and also to identify the potential effects of telmisartan, an angiotensin receptor blocker, we have used a mouse model of acute colitis induced by dextran sulphate sodium. We have used 0.01 and 5mg/kg body weight doses of telmisartan and administered as enema to facilitate the on-site action and to reduce the systemic adverse effects. Telmisartan high dose treatment significantly reduced the disease activity index score when compared with the colitis control mice. In addition, oxidative stress and endoplasmic reticulum stress markers expression were also significantly reduced when compared with the colitis control mice. Subsequent experiments were carried out to investigate some of the mechanisms underlying its anti-inflammatory effects and identified that the mRNA levels of pro-inflammatory cytokines such as tumour necrosis factor α, interleukin 1ß, interleukin 6 and monocyte chemoattractant protein 1 as well as cellular DNA damage were significantly suppressed when compared with the colitis control mice. Similarly the apoptosis marker proteins such as cleaved caspase 3 and 7 levels were down-regulated and anti-apoptotic protein Bcl2 level was significantly upregulated by telmisartan treatment. These results indicate that blockade of RAS by telmisartan can be an effective therapeutic option against acute colitis.

Tannic acid modulates NFκB signaling pathway and skin inflammation in NC/Nga mice through PPARγ expression.

Polyphenolic compound tannic acid, which is mainly found in grapes and green tea, is a potent antioxidant with anticarcinogenic activities. In this present study, we hypothesized that tannic acid could inhibit nuclear factor (NF)κB signaling and inflammation in atopic dermatitis (AD) NC/Nga mice. We have analyzed the effects of tannic acid on dermatitis severity, histopathology and expression of inflammatory signaling proteins in house dust mite extract induced AD mouse skin. In addition, serum levels of T helper (Th) cytokines (interferon (IFN)γ, interleukin (IL)-4) were measured by enzyme-linked immunosorbent assay. Treatment with tannic acid ameliorated the development of AD-like clinical symptoms and effectively inhibited hyperkeratosis, parakeratosis, acanthosis, mast cells and infiltration of inflammatory cells in the AD mouse skin. Serum levels of IFNγ and IL-4 were significantly down-regulated by tannic acid. Furthermore, tannic acid treatment inhibited DfE induced tumor necrosis factor (TNF)α, high mobility group protein (HMG)B1, receptor for advanced glycation end products (RAGE), extracellular signal-regulated kinase (ERK)1/2, NFκB, cyclooxygenase (COX)2, IL-1ß and increased the protein expression of peroxisome proliferator-activated receptor (PPAR)γ. Taken together, our results demonstrate that, DfE induced skin inflammation might be mediated through NFκB signaling and tannic acid may be a potential therapeutic agent for AD, which may possibly act via induction of PPARγ protein.

Modulation of HMGB1 translocation and RAGE/NFκB cascade by quercetin treatment mitigates atopic dermatitis in NC/Nga transgenic mice.

Quercetin, glycosylated form of flavonoid compound, has potent antioxidant and anti-inflammatory properties. In this study, we have investigated the effects of quercetin on skin lesion, high-mobility group box (HMGB)1 cascade signalling and inflammation in atopic dermatitis (AD) mouse model. AD-like lesion was induced by the application of house dust mite extract to the dorsal skin of NC/Nga transgenic mouse. After AD induction, quercetin (50 mg/kg, p.o) was administered daily for 2 weeks. We evaluated dermatitis severity, histopathological changes and changes in protein expression by Western blotting for HMGB1, receptor for advanced glycation end products (RAGE), toll-like receptor (TLR)4, nuclear factor (NF)κB, nuclear factor erythroid-2-related factor (Nrf)2, kelch-like ECH-associated protein (Keap)1, extracellular signal-regulated kinase (ERK)1/2, cyclooxygenase (COX)2, tumor necrosis factor (TNF)α, interleukin (IL)-1ß, IL-2Rα and other inflammatory markers in the skin of AD mice. In addition, serum levels of T helper (Th) cytokines (interferon (IFN)γ, IL-4) were measured by enzyme-linked immunosorbent assay. Quercetin treatment attenuated the development of AD-like skin lesions. Histological analysis showed that quercetin inhibited hyperkeratosis, parakeratosis, acanthosis, mast cells and infiltration of inflammatory cells. Furthermore, quercetin treatment downregulated cytoplasmic HMGB1, RAGE, nuclear p-NFκB, p-ERK1/2, COX2, TNFα, IL-1ß, IL-2Rα, IFNγ and IL-4 and upregulated nuclear Nrf2. Our data demonstrated that the HMGB1/RAGE/NFκB signalling might play an important role in skin inflammation, and quercetin treatment could be a promising agent for AD by modulating the HMGB1/RAGE/NFκB signalling and induction of Nrf2 protein.

Effect of carvedilol against myocardial injury due to ischemia-reperfusion of the brain in rats.

We have previously reported the mechanism behind the myocardial injury and the activation of autonomic nervous system during the ischemia-reperfusion (IR) of the rat brain. This study was planned to investigate the effect of carvedilol, a ß-blocker, in improving the myocardial injury caused by IR of the rat brain. We have used a whole cerebral IR model in rats by clamping both the right and left common carotid arteries. Rats were divided into five groups; Sham surgery group (Group-Sham), carvedilol treatment before ischemia group (Group-Is+C), vehicle control group (Group-Is+V), carvedilol treatment before reperfusion group (Group-Re+C) and the vehicle control group (Group-Re+V). We have measured the blood pressure and heart rate via a catheter, myocardial tissue ß1-adrenaline receptor (ß1-AR) levels, phosphor-p38 mitogen-activated protein kinase (p-p38 MAPK) signaling factor, malondialdehyde (MDA), and apoptosis (TUNEL assay and expression of caspase-7 protein). The results indicated that the increased expressions of ß1-AR, p-p38 MAPK, caspase-7, apoptotic cells and MDA level in the myocardial tissue due to brain ischemia-reperfusion were significantly reduced by carvedilol treatment. From these observations we can suggest that, with the advantage of its antioxidant and ß blocking action, carvedilol had played the improvement of myocardial injury in ischemia-reperfusion of the brain.

Pruni cortex ameliorates skin inflammation possibly through HMGB1-NFκB pathway in house dust mite induced atopic dermatitis NC/Nga transgenic mice.

Pruni cortex, the bark of Prunus jamasakura Siebold ex Koidzumi, has been used in the Japanese systems of medicine for many years for its anti-inflammatory, antioxidant and antitussive properties. In this study, we investigated the effect of pruni cortex on atopic dermatitis NC/Nga mouse model. Atopic dermatitis-like lesion was induced by the application of house dust mite extract to the dorsal skin. After induction of atopic dermatitis, pruni cortex aqueous extract (1 g/kg, p.o.) was administered daily for 2 weeks. We evaluated dermatitis severity, histopathological changes and cellular protein expression by Western blotting for nuclear and cytoplasmic high mobility group box 1, receptor for advanced glycation end products, nuclear factor κB, apoptosis and inflammatory markers in the skin of atopic dermatitis mice. The clinical observation confirmed that the dermatitis score was significantly lower when treated with pruni cortex than in the atopic dermatitis group. Similarly pruni cortex inhibited hypertrophy and infiltration of inflammatory cells as identified by histopathology. In addition, pruni cortex significantly inhibited the protein expression of cytoplasmic high mobility group box 1, receptor for advanced glycation end products, nuclear p-nuclear factor kappa B, apoptosis and inflammatory markers. These results indicate that pruni cortex may have therapeutic potential in the treatment of atopic dermatitis by attenuating high mobility group box 1 and inflammation possibly through the nuclear factor κB pathway.

Comparative evaluation of torasemide and furosemide on rats with streptozotocin-induced diabetic nephropathy.

Nephropathy is one of the complications of diabetes mellitus in human and experimental animals. There are various pathological renal remodeling processes leading to diabetic nephropathy because of the chronic hyperglycemia during diabetes mellitus. Various reports suggest the involvement of oxidative stress, inflammation and fibrosis during this progression. As antihypertensive drugs are reported to provide renoprotection in various animal models and clinical studies, we have carried out this study to identify the effect of torasemide, a loop diuretic, against streptozotocin-induced diabetic nephropathy and compare with furosemide. Here we have performed the measurement of blood and urine parameters and renal protein expression levels for measuring the disease severity in streptozotocin-induced diabetic rats treated torasemide or furosemide and compared with the vehicle treated rats. Furosemide treatment significantly increased the urinary protein excretion when compared with the normal rats. Torasemide treatment has reduced the expression of mineralocorticoid receptor and oxidative stress marker p67phox levels with improved mRNA levels of heme oxygenase-1 in the kidneys. In addition, torasemide treated diabetic rats showed significantly reduced expression of renal fibrosis related proteins when compared with the vehicle treated diabetic rats. Although furosemide treatment has produced improvement, its effects are comparably less than that of torasemide. Thus with the present results, we can suggest that torasemide treatment can improve the diabetic kidney disease in this rat model and which is superior to furosemide against renal fibrotic remodeling.

Beneficial effects of edaravone, a novel antioxidant, in rats with dilated cardiomyopathy.

Edaravone, a novel antioxidant, acts by trapping hydroxyl radicals, quenching active oxygen and so on. Its cardioprotective activity against experimental autoimmune myocarditis (EAM) was reported. Nevertheless, it remains to be determined whether edaravone protects against cardiac remodelling in dilated cardiomyopathy (DCM). The present study was undertaken to assess whether edaravone attenuates myocardial fibrosis, and examine the effect of edaravone on cardiac function in rats with DCM after EAM. Rat model of EAM was prepared by injection with porcine cardiac myosin 28 days after immunization, we administered edaravone intraperitoneally at 3 and 10 mg/kg/day to rats for 28 days. The results were compared with vehicle-treated rats with DCM. Cardiac function, by haemodynamic and echocardiographic study and histopathology were performed. Left ventricular (LV) expression of NADPH oxidase subunits (p47(phox), p67(phox), gp91(phox) and Nox4), fibrosis markers (TGF-ß(1) and OPN), endoplasmic reticulum (ER) stress markers (GRP78 and GADD 153) and apoptosis markers (cytochrome C and caspase-3) were measured by Western blotting. Edaravone-treated DCM rats showed better cardiac function compared with those of the vehicle-treated rats. In addition, LV expressions of NADPH oxidase subunits levels were significantly down-regulated in edaravone-treated rats. Furthermore, the number of collagen-III positive cells in the myocardium of edaravone-treated rats was lower compared with those of the vehicle-treated rats. Our results suggest that edaravone ameliorated the progression of DCM by modulating oxidative and ER stress-mediated myocardial apoptosis and fibrosis.

Involvement of AMPK and MAPK signaling during the progression of experimental autoimmune myocarditis in rats and its blockade using a novel antioxidant.

There are various reports suggesting the role of angiotensin (Ang) receptor blockers, Ang converting enzyme inhibitors, calcium channel blockers, diuretics and antioxidants against the progression of experimental autoimmune myocarditis (EAM) to dilated cardiomyopathy (DCM). Most of them were reported to be effective during this adverse cardiac remodeling. Recently much attention has been paid to studying the involvement of AMP-activated protein kinase (AMPK) and mitogen activated protein kinase (MAPK) in various cardiovascular ailments. AMPK acts as a master sensor of cellular energy balance via maintenance of lipid and glucose metabolism. Evidences also suggest the relation between AMPK and oxidative stress during physiological and pathological myocardial cellular function. Since, it is of interest to identify the roles of AMPK and MAPK during the progression of EAM to DCM and also the effect of edaravone, a novel free radical scavenger, against its progression. For this, we have carried out western blotting, histopathological staining and immunohistochemical analyses to measure the myocardial expressions of AMPK signaling and oxidative stress related parameters in normal and vehicle or edaravone-treated EAM rats, respectively. We identified the myocardial levels of phospho Akt and phosphoinositide 3-kinase, which are the upstream proteins of AMPK and MAPK activation and both were up-regulated in the vehicle-treated rats, whereas candesartan treatment significantly reversed these changes. We have also measured the myocardial levels of p-AMPKα, different isoforms of protein kinase C and MAPK signaling proteins. All of these protein levels were significantly elevated in the hearts of DCM rats whereas edaravone treatment significantly reversed these changes. In viewing these results, we can suggest that along with MAPK, AMPK signaling also plays a crucial role in the progression of EAM and it can be effectively blocked by the treatment with a novel antioxidant, edaravone.

Attenuation of CHOP-mediated myocardial apoptosis in pressure-overloaded dominant negative p38α mitogen-activated protein kinase mice.

BACKGROUND/AIMS: Pressure overload stimulation is known to elicit disturbances in the endoplasmic reticulum (ER), which leads to ER stress (ERS). p38 mitogen-activated protein kinase (MAPK) plays an important role in mediating apoptotic processes, however, the roles of this kinase in activating ERS-initiated apoptosis in pressure-overloaded hearts are largely unknown. METHODS: We clarified the role of p38α MAPK in ERS-associated apoptosis by subjecting transgenic mice displaying cardiac specific dominant negative (DN) mutant p38α MAPK over-expression to seven day pressure overload. RESULTS: Seven days pressure overload resulted in the same extent of cardiac hypertrophy and ERS in the wild-type (WT) and DN p38α mice compared with the sham mice. It also activated inositol-requiring enzyme (Ire)-1α and its downstream molecule, tumor necrosis factor receptor (TNFR)-associated factor (TRAF)2 in the WT and DN p38α mice compared with the sham mice. Interestingly, increased myocardial apoptosis and the up-regulation of CCAAT/enhancer binding protein homology protein (CHOP) expression compared with those in the sham mice were found in the aortic-banded WT mice, but not in the DN p38α mice. CONCLUSION: Partial inhibition of p38α protein blocked the activation of CHOP-mediated apoptotic processes during pressure overload by partially inhibiting signaling from the Ire-1α/TRAF2 to its down-stream molecule, CHOP.

Curcumin ameliorates cardiac inflammation in rats with autoimmune myocarditis.

Curcumin is a natural polyphenolic compound abundant in the rhizome of the perennial herb turmeric, Curcuma longa. It is commonly used as a dietary spice and coloring agent in cooking, and is used anecdotally as an herb in traditional Indian and Chinese medicine. It has been reported that curcumin has the potential to protect against cardiac inflammation through suppression of GATA-4 and nuclear factor-κB (NF-κB); however, no study to date has addressed the effect of curcumin on experimental autoimmune myocarditis (EAM) in rats. In this study, 8-week-old male Lewis rats were immunized with cardiac myosin to induce EAM. They were then divided randomly into a treatment or vehicle group and orally administrated curcumin (50 mg/kg/d) or 1% gum arabic, respectively, for 3 weeks after myosin injection. We performed hemodynamic, echocardiographic, hematoxylin and eosin staining, mast cell staining and Western blotting studies to evaluate the protective effect of curcumin in the acute phase of EAM. Cardiac functional parameters measured by hemodynamic and echocardiographic studies were significantly improved by curcumin treatment. Furthermore, curcumin reduced the heart weight-to-body weight ratio, area of inflammatory lesions and the myocardial protein level of NF-κB, interleukin (IL)-1ß, tumor necrosis factor (TNF)-α and GATA-4. Our results indicate that curcumin has the potential to protect against cardiac inflammation through suppression of IL-1ß, TNF-α, GATA-4 and NF-κB expresses, and may provide a novel therapeutic strategy for autoimmune myocarditis.

Le Carbone prevents liver damage in non-alcoholic steatohepatitis-hepatocellular carcinoma mouse model via AMPKα-SIRT1 signaling pathway activation.

Le Carbone (LC), a fiber-enriched activated charcoal dietary supplement, claimed to be effective against inflammation associated with colitis, trimethylaminuria, and sclerosis. The study aimed to investigate the underlying mechanisms of LC to protect liver damage and its progression in non-alcoholic steatohepatitis-hepatocellular carcinoma (NASH-HCC) mice. To induce this model, C57BL/6J male baby mice were injected with a low-dose of streptozotocin and fed with a high-fat diet (HFD) 32 during 4 weeks-16 weeks of age. The LC suspension was administered orally at a dose of 5 mg/mouse/day started at the age of 6 weeks and continued until 16 weeks of age along with HFD32 feeding. At the end of the experiment, serum and liver tissues were collected for the biochemical, histological, and molecular analysis. We found that LC suspension improved the histopathological changes, serum aminotransferases in NASH mice. The hepatic expression of metabolic proteins, p-AMPKα and sirtuin 1, and proteins responsible for ß-oxidation of fatty acids, peroxisome proliferator-activated receptor (PPAR) γ coactivator-α, PPARα were significantly repressed in NASH mice. LC treatment markedly restored these expressions. LC treatment significantly reduced the hepatic proteins expressions of PPARγ, tissue inhibitor of metalloproteinases 4, p47phox, p-JNK, p-ERK1/2, glypican-3, and prothrombin in NASH mice. Our findings demonstrate that LC prevents the liver damage and progression of NASH, possibly by enhancing the AMPK-SIRT1 signaling pathway.

Partial inactivation of cardiac 14-3-3 protein in vivo elicits endoplasmic reticulum stress (ERS) and activates ERS-initiated apoptosis in ERS-induced mice.

BACKGROUND/AIMS: Excessive endoplasmic reticulum stress (ERS) triggers apoptosis in various conditions including diabetic cardiomyopathy and pressure overload-induced cardiac hypertrophy and heart failure. The primary function of 14-3-3 protein is to inhibit apoptosis, but the roles of this protein in protecting against cardiac ERS and apoptosis are largely unknown. METHODS: We investigated the roles of 14-3-3 protein in vivo during cardiac ERS and apoptosis induced by pressure overload or thapsigargin injection using transgenic (TG) mice that showed cardiac-specific expression of dominant negative (DN) 14-3-3eta. RESULTS: Cardiac positive apoptotic cells and the expression of glucose-regulated protein (GRP)78, inositol-requiring enzyme (Ire)1alpha, tumor necrosis factor receptor (TNFR)-associated factor (TRAF)2, CCAAT/enhancer binding protein homology protein (CHOP), caspase-12, and cleaved caspase-12 protein were significantly increased in the pressure-overload induced DN 14-3-3eta mice compared with that in the WT mice. Furthermore, thapsigargin injection significantly increased the expression of GRP78 and TRAF2 expression in DN 14-3-3eta mice compared with that in the WT mice. CONCLUSION: The enhancement of 14-3-3 protein may provide a novel protective therapy against cardiac ERS and ERS-initiated apoptosis, at least in part, through the regulation of CHOP and caspase-12 via the Ire1alpha/TRAF2 pathway.

14-3-3 protein protects against cardiac endoplasmic reticulum stress (ERS) and ERS-initiated apoptosis in experimental diabetes.

Diabetic cardiomyopathy and nephropathy induce endoplasmic reticulum stress (ERS) and ERS-initiated apoptosis. The primary function of 14-3-3 protein is to inhibit apoptosis, but the roles of this protein in protecting against cardiac ERS and apoptosis in the diabetic heart are largely unknown. In this study, we investigated the in vivo role of 14-3-3 protein in diabetic ERS and apoptosis using streptozotocin (STZ)-induced transgenic mice that showed cardiac-specific expression of a dominant negative (DN) 14-3-3eta protein mutant. The expression levels of cardiac glucose-regulated protein (GRP) 78, inositol-requiring enzyme (Ire) 1alpha, and tumor necrosis factor receptor (TNFR)-associated factor (TRAF) 2 protein were significantly increased in the diabetic DN 14-3-3eta mice compared with the diabetic wild-type. Moreover, cardiac apoptosis and the expression of CCAAT/enhancer binding protein homology protein (CHOP), caspase-12, and cleaved caspase-12 protein were significantly increased in the diabetic DN 14-3-3eta mice. In conclusion, partial depletion of 14-3-3 protein in the diabetic heart exacerbates cardiac ERS and activates ERS-induced apoptosis pathways, at least in part, through the regulation of CHOP and caspase-12 via the Ire1alpha/TRAF2 pathway. The enhancement of 14-3-3 protein expression can be used as a novel protective therapy against ERS and ERS-initiated apoptosis in the diabetic heart.

Pharmacological Investigation of Ceraceomyces tessulatus (Agaricomycetes) in Mice with Nonalcoholic Steatohepatitis.

Nonalcoholic steatohepatitis (NASH) is becoming the most common cause of hepatocellular carcinoma (HCC). Natural products including edible mushrooms are gaining attention for the prevention and treatment of lifestyle related disorders. Ceraceomyces tessulatus (strain BDM-X) possesses potent antioxidative stress activity. In this study, we hypothesize that BDM-X treatment protects the liver of mouse with NASH by reducing inflammation in a novel NASH-HCC mouse model. C57BL/6J female pups were exposed to low-dose streptozotocin (STZ) and fed a high-fat diet (HFD) 32 from the age of 4 weeks to 16 weeks. Water extract of BDM-X was given at 500 mg/kg dose daily by oral gavage started at the age of 12 weeks and continued until 16 weeks of age along with HFD feeding. We found that BDM-X improved the histopathological changes, serum aminotransferases, and blood glucose levels in NASH mice. The hepatic protein expressions of SIRT1 and IL-10 were significantly repressed in NASH mice. BDM-X treatment restored these expressions. BDM-X treatment effectively reduced the progression of NASH by suppressing the protein expression of SREBPlc, p-NF-κB, Ep-CAM, and prothrombin in the NASH liver. In conclusion, our data suggest that BDM-X can protect the liver against inflammation and lipogenesis in NASH-HCC mice.

Brain adaptations of insulin signaling kinases, GLUT 3, p-BADser155 and nitrotyrosine expression in various hypoglycemic models of mice.

AIM AND OBJECTIVE: Insulin-induced moderate or severe hypoglycemia (MH or SH) impairs cognition and SH causes neuronal death. On the contrary, alternate day fasting (ADF) protects the brain during excitotoxic stress and improves cognitive function. Unlike the scenario in the periphery, insulin and its relationship towards brain glucose uptake and metabolism are considered to be less significant. Yet, the hypoglycemia associated brain metabolism is not clearly understood. The authors broadly investigated the brain metabolism in various hypoglycemic models such as insulin-induced MH, SH, SH with glucose reperfusion, 24 h fasting and ADF in the cortex or hippocampus of C57BL6/J mice. The authors analyzed the protein expression of insulin signaling kinases (plays a key role in neuronal survival and memory), Bcl-2 associated death promoter (p-BADser155) (dephosphorylation inhibits glucokinase activity and reduces glucose or increases ketone body metabolism in the brain), neuronal-specific glucose transporter 3 (GLUT 3) and nitrotyrosine (marker of nitric oxide which is involved in neuronal glucose uptake via GLUT 3) using western blotting analysis. RESULTS: Insulin-induced MH or SH differentially regulated the brain insulin signaling kinases. The expression of p-BADser155 decreased in all hypoglycemic models except the insulin-induced MH in hippocampus. The trended higher GLUT 3 and increased nitrotyrosine expression of insulin-induced SH were restored after glucose reperfusion. The trended higher or increased GLUT 3 and nitrotyrosine expression of ADF were positively correlated with serum beta-hydroxybutyrate levels. CONCLUSION: During hypoglycemia, it can be suggested that the brain might decrease glucose metabolism via glycolysis or prefer ketone body metabolism (except the insulin-induced MH in hippocampus) by modifying the p-BADser155 expression. In addition to the ketone body metabolism, the brain might adapt to uptake glucose in insulin-induced SH or ADF by modifying the GLUT 3 or nitrotyrosine expression.

[Effects of various diuretics on cardiac function in rats with heart failure].

Torasemide is a long-acting loop diuretic that combines the effects of both furosemide and spironolactone. It has been reported that torasemide but not furosemide might attenuate myocardial remodeling accompanied by left ventricular (LV) dysfunction. However, nothing is known about the effect of torasemide, long-acting loop diuretic and spironolactone, an aldosterone receptor antagonist in a rat model of chronic heart failure (CHF). Therefore, we compared the therapeutic effects of torasemide, furosemide and spironolactone on the progression of LV remodeling in a rat model of CHF after experimental autoimmune myocarditis (EAM). EAM was elicited in Lewis rats by immunization with porcine cardiac myosin. Twenty-eight days after immunization, rats were treated for 28 days with torasemide, furosemide and spironolactone. Diuretic actions, heart weight/body weight, heart rate, mean blood pressure, myocardial function by echocardiography, cardiac fibrosis, myocyte diameter and cardiac aldosterone synthetase (CYP11B2) were evaluated. Increased cardiac CYP11B2, severe LV remodeling and resultant cardiac dysfunction was found in CHF rats, whereas decreased cardiac CYP11B2, less remodeling and improvement of cardiac function were found in torasemide- and spironolactone-treated CHF rats. Our results indicate that torasemide and spironolactone treatment significantly improved cardiac function and LV remodeling compared with furosemide treatment.

Role of 14-3-3η protein on cardiac fatty acid metabolism and macrophage polarization after high fat diet induced type 2 diabetes mellitus.

Diabetic cardiomyopathy (DCM), a metabolic disorder, is one of the leading causes of mortality around the world and its pathogenesis involves cardiac inflammation and altered metabolic profile. Altered fatty acid metabolism during DCM can cause macrophage polarization in which inflammatory M1 phenotype dominates over the anti-inflammatory M2 phenotype. Hence, it is essential to identify a specific target, which could revert the metabolic profile and thereby reducing the M1 macrophage polarization. 14-3-3η protein has several cellular protective functions especially in the heart as plenty of reports available in various animal models of heart failure including diabetes mellitus. However, its role in the cardiac fatty acid metabolism and macrophage polarization remains unidentified. The present study has been designed to delineate the effect of cardiospecific dominant negative mutation of 14-3-3η protein (DN14-3-3) on various lipid metabolism related marker proteins expressions and cardiac macrophage phenotype in high fat diet (HFD) fed mice. Feeding HFD for 12 weeks has produced significant increase in body weight in the DN14-3-3 (TG) mice than C57BL6/J (WT) mice. Western blotting and immunohistochemical staining analysis of the heart tissue has revealed an increase in the expression of markers of cardiac fatty acid synthesis related proteins in addition to the reduced expression of fatty acid oxidation related proteins in TG mice fed HFD than WT mice fed HFD. Furthermore, the M1 macrophage marker proteins were increasingly expressed while M2 markers expressions were reduced in the hearts of TG mice fed HFD. In conclusion, our current study has identified that there is a definite role for the 14-3-3η protein against the pathogenesis of heart failure via regulation of cardiac fatty acid metabolism and macrophage polarization.