Kill two birds with one stone:Hapatologist’s approach to metabolic dysfunction-associated steatotic liver disease and heart failure

Heart failure(HF)is a major global public health concern,and one of the less commonly known risk factors for HF development is metabolic dysfunction-associated steatotic liver disease(MASLD),as they share a similar pathophysio-logical background.In this article,we evaluated a recently published review article by Arriola-Montenegro et al.This article briefly summarizes the common pathophysiology of HF and MASLD development and evaluates the available therapeutic options to treat both conditions.Clinical practice guidelines highlight the importance of initiating and titrating guideline-directed medication therapy(GDMT)for patients with HF with reduced ejection fraction.GDMT is comprised of the four pillars currently proposed in most clinical practice guidelines,namely angiotensin-converting enzyme inhibitors(ACEIs),angiotensin receptor blockers(ARBs),angiotensin receptor-neprilysin inhibitors,beta-blockers,mineralocor-ticoid receptor antagonists,and sodium-glucose co-transporter 2 inhibitors(SGLT-2i).Given the similarity of pathophysiology and risk factors,recent studies for GDMT regarding ACEIs,ARBs,mineralocorticoid receptor antagonists,and SGLT-2i have shown beneficial effects on MASLD.Nonetheless,other medications for both conditions and novel therapies require more robust data and well-designed clinical studies to demonstrate their efficacies in both conditions.

Mitochondrial dysfunction affects hepatic immune and metabolic remodeling in patients with hepatitis B virus-related acute-onchronic liver failure

BACKGROUND Immune dysregulation and metabolic derangement have been recognized as key factors that contribute to the progression of hepatitis B virus(HBV)-related acute-on-chronic liver failure(ACLF).However,the mechanisms underlying immune and metabolic derangement in patients with advanced HBV-ACLF are unclear.AIM To identify the bioenergetic alterations in the liver of patients with HBV-ACLF causing hepatic immune dysregulation and metabolic disorders.METHODS Liver samples were collected from 16 healthy donors(HDs)and 17 advanced HBV-ACLF patients who were eligible for liver transplantation.The mitochondrial ultrastructure,metabolic characteristics,and immune microenvironment of the liver were assessed.More focus was given to organic acid metabolism as well as the function and subpopulations of macrophages in patients with HBV-ACLF.RESULTS Compared with HDs,there was extensive hepatocyte necrosis,immune cell infiltration,and ductular reaction in patients with ACLF.In patients,the liver suffered severe hypoxia,as evidenced by increased expression of hypoxia-inducible factor-1α.Swollen mitochondria and cristae were observed in the liver of patients.The number,length,width,and area of mitochondria were adaptively increased in hepatocytes.Targeted metabolomics analysis revealed that mitochondrial oxidative phosphorylation decreased,while anaerobic glycolysis was enhanced in patients with HBV-ACLF.These findings suggested that,to a greater extent,hepa-tocytes used the extra-mitochondrial glycolytic pathway as an energy source.Patients with HBV-ACLF had elevated levels of chemokine C-C motif ligand 2 in the liver homogenate,which stimulates peripheral monocyte infiltration into the liver.Characterization and functional analysis of macrophage subsets revealed that patients with ACLF had a high abundance of CD68^(+)HLA-DR^(+)macrophages and elevated levels of both interleukin-1βand transforming growth factor-β1 in their livers.The abundance of CD206^(+)CD163^(+)macrophages and expression of interleukin-10 decreased.The correlation analysis revealed that hepatic organic acid metabolites were closely associated with macrophage-derived cytokines/chemokines.CONCLUSION The results indicated that bioenergetic alteration driven by hypoxia and mitochondrial dysfunction affects hepatic immune and metabolic remodeling,leading to advanced HBV-ACLF.These findings highlight a new therapeutic target for improving the treatment of HBV-ACLF.

Novel insights into autophagy in gastrointestinal pathologies,mechanisms in metabolic dysfunction-associated fatty liver disease and acute liver failure

In this editorial,we comment on three articles published in a recent issue of World Journal of Gastroenterology.There is a pressing need for new research on autophagy's role in gastrointestinal(GI)disorders,and also novel insights into some liver conditions,such as metabolic dysfunction-associated fatty liver disease(MAFLD)and acute liver failure(ALF).Despite advancements,understanding autophagy's intricate mechanisms and implications in these diseases remains incomplete.Moreover,MAFLD's pathogenesis,encompassing hepatic steatosis and metabolic dysregulation,require further elucidation.Similarly,the mechanisms underlying ALF,a severe hepatic dysfunction,are poorly understood.Innovative studies exploring the interplay between autophagy and GI disorders,as well as defined mechanisms of MAFLD and ALF,are crucial for identifying therapeutic targets and enhancing diagnostic and treatment strategies to mitigate the global burden of these diseases.

Navigating Long-Term Management Challenges in Short Bowel Syndrome: A Case Report of Chronic Intestinal Failure Complicated by Kidney Dysfunction

The most common cause of intestinal failure is short bowel syndrome (SBS), occurring as a result of a small functional intestine length, usually less than 200 cm, leading to intestinal malabsorption. A 59-year-old female with a past medical history of Crohns disease status post total colectomy with ileostomy over 20 years ago came to the hospital due to progressive weakness. Despite medical management, the patient had high ileostomy output, leading to electrolyte disbalance, metabolic acidosis, dehydration, and progressive kidney decline. Due to the high dependence on continuous fluid supplementation, it was decided to place a port for parenteral hydration to maintain fluid replacements and homeostasis after discharge. Prompt initiation of parenteral fluid replacement and close follow-up on patients with ileostomy and intestinal failure is strongly recommended to avoid complications and prevent intestinal, liver, or kidney transplants.

Alpha-synuclein in mitochondrial dysfunction:opportunities or obstacles

Recent work suggests a link betweenα-synuclein(α-syn)and mitochondrial dysfunction;however,the mechanisms of howα-syn influences mitochondrial function are still unclear.Most notably,whetherα-syn plays a direct role during mitochondrial function and/or whether diseasedα-syn-mediated mitochondrial dysfunction is a potential modifiable risk factor in Parkinson’s disease(PD)is unknown.To date,mutations in more than eight genes cause familial PD(fPD)and have functions in diverse pathways including synaptic homeostasis,mitochondria maintenance,autophagy/lysosome,and ubiquitin-proteasome pathways.

Fibrinogen’s potential role in connecting cerebrovascular abnormalities with glymphatic dysfunction in Alzheimer’s disease

Alzheimer’s disease(AD)stands out as the primary manifestation of age-related dementia,portraying a chronic neurodegenerative disorder distinguished by the accumulation of fibrillar amyloid-β(Aβ)plaques and neurofibrillary tangles of hyperphosphorylated tau.However,from a clinical standpoint,AD presents itself as a complex condition with a spectrum of dysfunctions rather than a singular pathological mechanism.An often-overlooked aspect of the disease is the presence of extensive cerebrovascular abnormalities,given that the majority of AD patients experience altered cerebral blood flow,damaged vasculature,increased microinfarcts and microhemorrhages.Animal models of AD further support this observation,showing cerebrovascular dysfunction such as impaired cerebral blood flow and altered cerebrovascular reactivity(Tataryn et al.,2021;Gareau et al.,2023).

Interleukin 1βreceptor and synaptic dysfunction in recurrent brain infection with Herpes simplex virus type-1

Several experimental evidence suggests a link between brain Herpes simplex virus type-1 infection and the occurrence of Alzheimer’s disease.However,the molecular mechanisms underlying this association are not completely understood.Among the molecular mediators of synaptic and cognitive dysfunction occurring after Herpes simplex virus type-1 infection and reactivation in the brain neuroinflammatory cytokines seem to occupy a central role.Here,we specifically reviewed literature reports dealing with the impact of neuroinflammation on synaptic dysfunction observed after recurrent Herpes simplex virus type-1 reactivation in the brain,highlighting the role of interleukins and,in particular,interleukin 1βas a possible target against Herpes simplex virus type-1-induced neuronal dysfunctions.

The emerging role of nitric oxide in the synaptic dysfunction of vascular dementia

With an increase in global aging,the number of people affected by cerebrovascular diseases is also increasing,and the incidence of vascular dementia-closely related to cerebrovascular risk-is increasing at an epidemic rate.However,few therapeutic options exist that can markedly improve the cognitive impairment and prognosis of vascular dementia patients.Similarly in Alzheimer’s disease and other neurological disorders,synaptic dysfunction is recognized as the main reason for cognitive decline.Nitric oxide is one of the ubiquitous gaseous cellular messengers involved in multiple physiological and pathological processes of the central nervous system.Recently,nitric oxide has been implicated in regulating synaptic plasticity and plays an important role in the pathogenesis of vascular dementia.This review introduces in detail the emerging role of nitric oxide in physiological and pathological states of vascular dementia and summarizes the diverse effects of nitric oxide on different aspects of synaptic dysfunction,neuroinflammation,oxidative stress,and blood-brain barrier dysfunction that underlie the progress of vascular dementia.Additionally,we propose that targeting the nitric oxide-sGC-cGMP pathway using certain specific approaches may provide a novel therapeutic strategy for vascular dementia.

Recombinant chitinase-3-like protein 1 alleviates learning and memory impairments via M2 microglia polarization in postoperative cognitive dysfunction mice

Postoperative cognitive dysfunction is a seve re complication of the central nervous system that occurs after anesthesia and surgery,and has received attention for its high incidence and effect on the quality of life of patients.To date,there are no viable treatment options for postoperative cognitive dysfunction.The identification of postoperative cognitive dysfunction hub genes could provide new research directions and therapeutic targets for future research.To identify the signaling mechanisms contributing to postoperative cognitive dysfunction,we first conducted Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses of the Gene Expression Omnibus GSE95426 dataset,which consists of mRNAs and long non-coding RNAs differentially expressed in mouse hippocampus3 days after tibial fracture.The dataset was enriched in genes associated with the biological process"regulation of immune cells,"of which Chill was identified as a hub gene.Therefore,we investigated the contribution of chitinase-3-like protein 1 protein expression changes to postoperative cognitive dysfunction in the mouse model of tibial fractu re surgery.Mice were intraperitoneally injected with vehicle or recombinant chitinase-3-like protein 124 hours post-surgery,and the injection groups were compared with untreated control mice for learning and memory capacities using the Y-maze and fear conditioning tests.In addition,protein expression levels of proinflammatory factors(interleukin-1βand inducible nitric oxide synthase),M2-type macrophage markers(CD206 and arginase-1),and cognition-related proteins(brain-derived neurotropic factor and phosphorylated NMDA receptor subunit NR2B)were measured in hippocampus by western blotting.Treatment with recombinant chitinase-3-like protein 1 prevented surgery-induced cognitive impairment,downregulated interleukin-1βand nducible nitric oxide synthase expression,and upregulated CD206,arginase-1,pNR2B,and brain-derived neurotropic factor expression compared with vehicle treatment.Intraperitoneal administration of the specific ERK inhibitor PD98059 diminished the effects of recombinant chitinase-3-like protein 1.Collectively,our findings suggest that recombinant chitinase-3-like protein 1 ameliorates surgery-induced cognitive decline by attenuating neuroinflammation via M2 microglial polarization in the hippocampus.Therefore,recombinant chitinase-3-like protein1 may have therapeutic potential fo r postoperative cognitive dysfunction.

King's College criteria and the Clichy-Villejuif criteria require adjustments for assessing acute liver failure due to yellow fever

BACKGROUND Acute liver failure(ALF)is a severe condition characterized by rapid deterioration of liver function in individuals without preexisting liver disease.Liver transplantation(LT)is the most impactful treatment.Yellow fever(YF)is an infectious disease that primarily affects the liver and has a high mortality rate.However,LT can be a viable option for treating rare cases with extensive liver involvement.However,the criteria for assessing the severity of ALF and determining the indications for transplantation have not been specifically validated for cases caused by YF.AIM To present necessary adjustments to established scoring systems for ALF secondary to YF.METHODS This was an observational,retrospective,single-center study.Fourteen consecutive patients with confirmed ALF due to YF were monitored in the intensive care unit by a specialized liver transplant team during a three-month epidemic outbreak in Brazil.During hospitalization,general supportive therapeutic measures were implemented,and the patients were regularly assessed using the King's College criteria and the Clichy-Villejuif criteria to determine the severity of liver failure.LT is considered a viable measure for patients with signs of end-stage liver failure.RESULTS Eight of 14(57%)patients developed severe neurological alterations within the first 96 hours after hospital admission.Four patients underwent emergency LT,and despite a moderate viral infection of the graft after transplantation,the 5-year survival rate was 50%.Although the King's College criteria and the Clichy-Villejuif criteria are the main scoring systems for ALF,they are insufficient for predicting the risk of mortality in this context,primarily because of low serum bilirubin levels in the final stage of the disease and significant disparities between coagulation abnormalities and patient severity.CONCLUSION To ensure good applicability in cases of YF-induced ALF,the authors suggest adaptations to the King's College and Clichy-Villejuif criteria.

Endothelial dysfunction in the kidney transplant population:Current evidence and management strategies

The endothelium modulates vascular homeostasis owing to a variety of vasoconstrictors and vasodilators.Endothelial dysfunction(ED),characterized by impaired vasodilation,inflammation,and thrombosis,triggers future cardiovascular(CV)diseases.Chronic kidney disease,a state of chronic inflammation caused by oxidative stress,metabolic abnormalities,infection,and uremic toxins damages the endothelium.ED is also associated with a decline in estimated glomerular filtration rate.After kidney transplantation,endothelial functions undergo immediate but partial restoration,promising graft longevity and enhanced CV health.However,the anticipated CV outcomes do not happen due to various transplant-related and unrelated risk factors for ED,culminating in poor CV health and graft survival.ED in kidney transplant recipients is an underrecognized and poorly studied entity.CV diseases are the leading cause of death among kidney transplant candidates with functioning grafts.ED contributes to the pathogenesis of many of the CV diseases.Various biomarkers and vasoreactivity tests are available to study endothelial functions.With an increasing number of transplants happening every year,and improved graft rejection rates due to the availability of effective immunosuppressants,the focus has now shifted to endothelial protection for the prevention,early recognition,and treatment of CV diseases.

Heart failure and left ventricular dysfunction in older patients with chronic kidney disease: the China Hypertension Survey (2012‒2015)

Background Heart failure(HF)is a leading cause of hospitalization and mortality for older chronic kidney disease(CKD)patients.However,the epidemiological data is scarce.We aimed to determine the prevalence of left ventricular(LV)dysfunction and HF,and to explore the risk factors for HF among those patients.Methods This is a cross-sectional analysis of the China Hypertension Survey conducted between October 2012 and December 2015.A total of 5,808 participants aged≥65 years were included in the analysis.Self-reported history of HF and any other cardiovascular diseases was acquired.2-D and Doppler echocardiography were used to assess LV dysfunction.CKD was defined as either estimated glomerular filtration rate(eGFR)<60 mL/min per 1.73 m2 or urinary albumin to creatinine ratio(ACR)≥30 mg/g.Results Among CKD patients aged≥65 years,the weighted prevalence of HF,heart failure with preserved ejection fraction(HFpEF),heart failure with mid-range ejection fraction(HFmrEF),and heart failure with reduced ejection fraction(HFrEF)was 4.8%,2.5%,0.8%,and 1.7%,respectively.The weighted prevalence of HF was 5.0%in patients with eGFR<60 mL/min per 1.73 m2,and was 5.9%in patients with ACR≥30 mg/g.The prevalence of LV systolic dysfunction was 3.1%,and while it was 8.9%for moderate/severe diastolic dysfunction.Multivariate analysis showed that smoking was significantly associated with the risk of HF.Furthermore,age,smoking,and residents in rural areas were significantly associated with a risk of LV diastolic dysfunction.Conclusions The prevalence of HF and LV dysfunction was high in older patients with CKD,suggesting that particular strategies will be required.

Study on the effect and mechanism of the dysfunction of CD4^+ T cells in the disease process of chronic cardiac failure

Objective: To study the effect and mechanism of the dysfunction of CD4+ T cells in the disease process of chronic cardiac failure (CHF).Methods:According to different group technologies, 100 CHF patients were divided into the following groups: ischemia group and non-ischemia group, heart function Ⅰ-Ⅱ group and heart function Ⅲ-Ⅳ group, event group and non-event group, and 50 healthy volunteers were included in the control group. Realtime PCR was used to detect transcription factors T-bet and GATA-3 of Th1 and Th2; flow cytometry was applied to determine the ratio of Th17 and Treg cells; ELISA was employed to test cytokines IFN-γ, IL-4, IL-17 and IL-10 of peripheral blood Th1, Th2, Th17 and Treg cells, respectively; ultrasonic cardiogram was used to exploit to LVEF and LVEDd; and electrochemilu minescene immunoassay was used to examine plasma BNP. The differences of all indexes of all groups were analyzed and the correlation between CD4 T cells and clinical indexes was analyzed by Pearson correlation analysis. Results: As compared to the control group, the transcription factors T-bet and GATA-3 of Th1 and Th2, the ratio of cytokines Th17 and IFN-γ, cytokines IL-17, T-bet/GATA-3, IFN-γ/IL-4, Th17 cells/Treg cells, IL-17/IL-10 of the ischemia group and non-ischemia group, heart functionⅠ-Ⅱgroup and heart function Ⅲ-Ⅳ group, event group and non-event group were all increased significantly, while their transcription factor GATA-3 of Th2, cytokines IL4, Treg cells ratio, cytokines IL10 were decreased obviously. The differences showed statistical significance (P < 0.05). The increase or decrease of the partial CD4+ T cells of the ischemia group, heart function Ⅲ-Ⅳ group and event group was more distinctly. The results of Pearson correlation analysis showed that IFN-γ and IL-17 were significantly positively correlated with LVEDd and BNP, IL-4 and IL-10 were also significantly positively correlated with LVEF, but correlated negatively with BNP, and IL-17 was negatively correlative with LVEF. Conclusions: There was a correlation between CHF and the dysfunction of CD4+ T cells showing immune activation phenomenons of deviations from the Th1/Th2 balance towards Th1 and from the Th17/Treg balance towards Th17, which was also related to the types, severity and prognosis of the disease.

Effects of exercise training on diastolic and systolic dysfunction in patients with chronic heart failure

BACKGROUND Chronic heart failure(CHF)is a complex syndrome characterized by a progressive reduction of the left ventricular(LV)contractility,low exercise tolerance,and increased mortality and morbidity.Diastolic dysfunction(DD)of the LV,is a keystone in the pathophysiology of CHF and plays a major role in the progression of most cardiac diseases.Also,it is well estimated that exercise training induces several beneficial effects on patients with CHF.AIM To evaluate the impact of a cardiac rehabilitation program on the DD and LV ejection fraction(EF)in patients with CHF.METHODS Thirty-two stable patients with CHF(age:56±10 years,EF:32%±8%,88%men)participated in an exercise rehabilitation program.They were randomly assigned to aerobic exercise(AER)or combined aerobic and strength training(COM),based on age and peak oxygen uptake,as stratified randomization criteria.Before and after the program,they underwent a symptom-limited maximal cardiopulmonary exercise testing(CPET)and serial echocardiography evaluation to evaluate peak oxygen uptake(VO2peak),peak workload(Wpeak),DD grade,right ventricular systolic pressure(RVSP),and EF.RESULTS The whole cohort improved VO2peak,and Wpeak,as well as DD grade(P<0.05).Overall,9 patients(28.1%)improved DD grade,while 23(71.9%)remained at the same DD grade;this was a significant difference,considering DD grade at baseline(P<0.05).In addition,the whole cohort improved RVSP and EF(P<0.05).Not any between-group differences were observed in the variables assessed(P>0.05).CONCLUSION Exercise rehabilitation improves indices of diastolic and systolic dysfunction.Exercise protocol was not observed to affect outcomes.These results need to be further investigated in larger samples.

Beta-blocker therapy in elderly patients with renal dysfunction and heart failure

OBJECTIVE To assess the role of beta-blockers(BB)in patients with chronic kidney disease(CKD)aged≥75 years.METHODS AND RESULTS From January 2008 to July 2014,we included 390 consecutive patients≥75 years of age with ejection fraction≤35%and glomerular filtration rate(GFR)≤60 m L/min per 1.73 m^2.We analyzed the relationship between treatment with BB and mortality or cardiovascular events.The mean age of our population was 82.6±4.1 years.Mean ejection fraction was 27.9%±6.5%.GFR was 60-45 m L/min per 1.73 m^2 in 50.3%of patients,45-30 m L/min per 1.73 m^2 in 37.4%,and<30 m L/min per 1.73 m^2 in 12.3%.At the conclusion of follow-up,67.4%of patients were receiving BB.The median follow-up was28.04(IR:19.41-36.67)months.During the study period,211 patients(54.1%)died and 257(65.9%)had a major cardiovascular event(death or hospitalization for heart failure).BB use was significantly associated with a reduced risk of death(HR=0.51,95%CI:0.35-0.74;P<0.001).Patients receiving BB consistently showed a reduced risk of death across the different stages of CKD:stage IIIa(GFR=30-45 m L/min per 1.73 m^2;HR=0.47,95%CI:0.26-0.86,P<0.0001),stage IIIb(GFR 30-45 m L/min per 1.73 m^2;HR=0.55,95%CI:0.26-1.06,P=0.007),and stages IV and V(GFR<30 m L/min per 1.73 m~2;HR=0.29,95%CI:0.11-0.76;P=0.047).CONCLUSIONS The use of BB in elderly patients with HFr EF and renal impairment was associated with a better prognosis.Use of BB should be encouraged when possible.

Combined use of non-biological artif icial liver treatments for patients with acute liver failure complicated by multiple organ dysfunction syndrome

BACKGROUND:Acute liver failure(ALF) caused by viral and non-viral hepatitis is often accompanied with severe metabolic disorders,the accumulation of toxic substances and continuous release and accumulation of a large number of endogenous toxins and inflammatory mediators. The present study aimed to investigate the effects of various combined non-biological artif icial liver treatments for patients with acute liver failure(ALF) complicated by multiple organ dysfunction syndrome(MODS).METHODS:Thirty-one patients with mid- or late-stage liver failure complicated by MODS(score 4) were randomly divided into three treatment groups:plasmapheresis(PE) combined with hemoperfusion(HP) and continuous venovenous hemodiafiltration(CVVHDF),PE+CVVHDF,and HP+CVVHDF,respectively. Heart rate(HR) before and after treatment,mean arterial pressure(MAP),respiratory index(PaO2/FiO2),hepatic function,platelet count,and blood coagulation were determined.RESULTS:Signifi cant improvement was observed in HR,MAP,PaO2/FiO2,total bilirubin(TBIL) and alanine aminotransferase(ALT) levels after treatment(P<0.05). TBIL and ALT decreased more signifi cantly after treatment in the PE+CVVHDF and PE+HP+CVVHDF groups(P<0.01). Prothrombin time(PT) and albumin were signifi cantly improved only in the PE+CVVHDF and PE+HP+CVVHDF groups(P<0.05). TBIL decreased more significantly in the PE+HP+CVVHDF group than in the HP+CVVHDF and PE+CVVHDF groups(P<0.05). The survival rate of the patients was 58.1%(18/31),viral survival rate 36.4%(4/11),and non-viral survival rate 70%(14/20).CONCLUSION:Liver function was relatively improved after treatment,but PE+HP+CVVHDF was more efficient for the removal of toxic metabolites,especially bilirubin. The survival rate was signifi cantly higher in the patients with non-viral liver failure than in those with viral liver failure.

Deciphering the role of PGC-1α in neurological disorders: from mitochondrial dysfunction to synaptic failure

The onset and mechanisms underlying neurodegenerative diseases remain uncertain. The main features of neurodegenerative diseases have been related with cellular and molecular events like neuronal loss, mitochondrial dysfunction and aberrant accumulation of misfolded proteins or peptides in specific areas of the brain. The most prevalent neurodegenerative diseases belonging to age-related pathologies are Alzheimer's disease, Huntington's disease, Parkinson's disease and amyotrophic lateral sclerosis. Interestingly, mitochondrial dysfunction has been observed to occur during the early onset of several neuropathological events associated to neurodegenerative diseases. The master regulator of mitochondrial quality control and energetic metabolism is the transcriptional coactivator peroxisome proliferator-activated receptor gamma coactivator 1-alpha(PGC-1α). Additionally, it has been observed that PGC-1α appears to be a key factor in maintaining neuronal survival and synaptic transmission. In fact, PGC-1α downregulation in different brain areas(hippocampus, substantia nigra, cortex, striatum and spinal cord) that occurs in function of neurological damage including oxidative stress, neuronal loss, and motor disorders has been seen in several animal and cellular models of neurodegenerative diseases. Current evidence indicates that PGC-1α upregulation may serve as a potent therapeutic approach against development and progression of neuronal damage. Remarkably, increasing evidence shows that PGC-1α deficient mice have neurodegenerative diseases-like features, as well as neurological abnormalities. Finally, we discuss recent studies showing novel specific PGC-1α isoforms in the central nervous system that appear to exert a key role in the age of onset of neurodegenerative diseases and have a neuroprotective function in the central nervous system, thus opening a new molecular strategy for treatment of neurodegenerative diseases. The purpose of this review is to provide an up-to-date overview of the PGC-1α role in the physiopathology of neurodegenerative diseases, as well as establish the importance of PGC-1α function in synaptic transmission and neuronal survival.

Skeletal muscle atrophy,regeneration,and dysfunction in heart failure:Impact of exercise training

This review highlights some established and some more contemporary mechanisms responsible for heart failure(HF)-induced skeletal muscle wasting and weakness.We first describe the effects of HF on the relationship between protein synthesis and degradation rates,which determine muscle mass,the involvement of the satellite cells for continual muscle regeneration,and changes in myofiber calcium homeostasis linked to contractile dysfunction.We then highlight key mechanistic effects of both aerobic and resistance exercise training on skeletal muscle in HF and outline its application as a beneficial treatment.Overall,HF causes multiple impairments related to autophagy,anabolic-catabolic signaling,satellite cell proliferation,and calcium homeostasis,which together promote fiber atrophy,contractile dysfunction,and impaired regeneration.Although both wasting and weakness are partly rescued by aerobic and resistance exercise training in HF,the effects of satellite cell dynamics remain poorly explored.

Left and right ventricular diastolic dysfunction and diastolic heart failure: does one lead to the other?

Background and Objective Diastolic dysfunction of the left ventricle is a mechanical abnormality diagnosed primarily by echocardiogram, and can be distinguished into three separate degrees based on the severity of reduction in passive compliance and active myocardial relaxation. Methods A literature search was performed for basic science studies, clinical studies and major practice guidelines on the subject of diastolic dysfunction and diastolic heart failure. Important findings were analyzed and correlated with regard to clinical relevance. Results Left ventricular diastolic dysfunction appears to compromise exercise tolerance and is believed to contribute to the pathophysiology in patients with diastolic heart failure. In the clinical setting, however, oftentimes no clear distinction is made between echocardiographically diagnosed diastolic dysfunction and diastolic heart failure, and adequate treatment recommendations are sparse and aimed to prevent worsening and progression of clinical symptoms. To date, there is a lack of high powered trials assessing the possible progression rate from echocardiographically diagnosed diastolic dysfunction to the clinical diagnosis of diastolic heart failure. Furthermore, there are no solid indices to assess the degree of severity of diastolic dysfunction or its progression. Pure right ventricular diastolic dysfunction appears to be even less understood and under-recognized, although it may play a role in the development of both right and left heart failure. Currently there are few but interesting data on the possible interaction between ventricles with diastolic dysfunction and the overall affect on the development of heart failure. Conclusions The timeline and progression of diastolic dysfunction to diastolic heart failure have not been well established and warrant further investigation.

Role of imaging in the evaluation of renal dysfunction in heart failure patients

Heart failure and kidney disease share common pathophysiological pathways which can lead to mutual dysfunction,known as cardiorenal syndrome.In heart failure patients,renal impairment is related to hemodynamic and nonhemodynamic factors.Both decreased renal blood flow and renal venous congestion due to heart failure could lead to impaired renal function.Kidney disease and worsening renal function are independently associated with poor prognosis in heart failure patients,both in acute and chronic clinical settings.The aim of this review is to assess the role of renal imaging modalities in the evaluation and management of heart failure patients.Renal imaging techniques could complete laboratory data,as estimated glomerular filtration rate,exploring different pathophysiological factors involved in kidney disease and adding valuable information about renal structure and function.In particular,Doppler examination of arterial and venous hemodynamics is a feasible and non invasive technique,which has proven to be a reliable method for prognostic stratification in patients with cardiorenal syndrome.The renal resistance index,a measure related to renal hemodynamics,can be calculated from the Doppler evaluation of arterial flow.Moreover,the analysis of Doppler venous flow patterns can integrate information from the arterial study and evaluate renal congestion.Other imaging modalities are promising,but still confined to research purposes.